diff --git a/src/app/qt/view/QtGraphView.cpp b/src/app/qt/view/QtGraphView.cpp
index f7585901..11d67f89 100644
--- a/src/app/qt/view/QtGraphView.cpp
+++ b/src/app/qt/view/QtGraphView.cpp
@@ -246,7 +246,7 @@ std::shared_ptr<QtGraphEdge> QtGraphView::createEdge(QGraphicsView* view, const
 	}
 	else
 	{
-		LOG_WARNING("Couldn't find owner or target node.");
+		LOG_WARNING_STREAM(<< "Couldn't find owner or target node for edge: " << edge.data->getName());
 		return NULL;
 	}
 }
diff --git a/src/app/qt/view/graphElements/QtGraphEdge.cpp b/src/app/qt/view/graphElements/QtGraphEdge.cpp
index 9a79a37e..41a3ae85 100644
--- a/src/app/qt/view/graphElements/QtGraphEdge.cpp
+++ b/src/app/qt/view/graphElements/QtGraphEdge.cpp
@@ -1,68 +1,86 @@
 #include "qt/view/graphElements/QtGraphEdge.h"
 
+#include <cmath>
+
 #include <QGraphicsScene>
 #include <QGraphicsSceneEvent>
 #include <QPainter>
 #include <QPen>
 
+#include "utility/messaging/type/MessageActivateToken.h"
+#include "utility/messaging/type/MessageActivateTokens.h"
+
 #include "component/view/graphElements/GraphNode.h"
+#include "data/graph/token_component/TokenComponentAggregation.h"
+#include "qt/graphics/QtGraphicsRoundedRectItem.h"
 
-
-QtStraightConnection::QtStraightConnection(Vec4i ownerRect, Vec4i targetRect, QGraphicsItem* parent)
+QtStraightConnection::QtStraightConnection(Vec4i ownerRect, Vec4i targetRect, int number, QGraphicsItem* parent)
 	: QGraphicsLineItem(parent)
 {
 	const Vec4i& o = ownerRect;
 	const Vec4i& t = targetRect;
 
-	Vec2f po[2] = { Vec2f(o.x, (o.y + 2 * o.w) / 3), Vec2f(o.z, (o.y + 2 * o.w) / 3) };
-	Vec2f pt[2] = { Vec2f(t.x, (2 * t.y + t.w) / 3), Vec2f(t.z, (2 * t.y + t.w) / 3) };
+	Vec2f a((o.x + o.z) / 2, (o.y + o.w) / 2);
+	Vec2f b((t.x + t.z) / 2, (t.y + t.w) / 2);
 
-	int io = -1;
-	int it = -1;
-	float dist = -1;
-
-	for (int i = 0; i < 2; i++)
-	{
-		for (int j = 0; j < 2; j++)
-		{
-			Vec2f diff = po[i] - pt[j];
-			if (dist < 0 || diff.getLength() < dist)
-			{
-				dist = diff.getLength();
-				io = i;
-				it = j;
-			}
-		}
-	}
-
-	this->setLine(po[io].x, po[io].y, pt[it].x, pt[it].y);
+	this->setLine(a.x, a.y, b.x, b.y);
 	this->setAcceptHoverEvents(true);
+
+	Vec2f u = b - a;
+	u.normalize();
+
+	float alpha = atan2(u.y, u.x);
+
+	Vec2f w;
+	w.x = (o.z - o.x) / 2 * cos(alpha);
+	w.y = (o.w - o.y) / 2 * sin(alpha);
+	a += u * w.getLength();
+
+	w.x = (t.z - t.x) / 2 * cos(alpha);
+	w.y = (t.w - t.y) / 2 * sin(alpha);
+	b += u * -w.getLength();
+
+	Vec2f mid = (a + b) / 2;
+
+	m_circle = new QtGraphicsRoundedRectItem(this);
+	m_circle->setRect(mid.x - 10, mid.y - 10, 20, 20);
+	m_circle->setRadius(10);
+	m_circle->setPen(QPen(QColor("#F8F8F8"), 2));
+	m_circle->setBrush(QBrush(QColor("#FFF")));
+	m_circle->setAcceptHoverEvents(true);
+
+	QFont font;
+	font.setFamily("Myriad Pro");
+	font.setWeight(QFont::Normal);
+	font.setPixelSize(9);
+
+	m_number = new QGraphicsSimpleTextItem(this);
+	m_number->setFont(font);
+
+	QString numberStr = QString::number(number);
+	m_number->setText(numberStr);
+	m_number->setBrush(QBrush(QColor("#666")));
+	m_number->setPos(
+		mid.x - QFontMetrics(m_number->font()).width(numberStr) / 2,
+		mid.y - QFontMetrics(m_number->font()).height() / 2
+	);
 }
 
 QtStraightConnection::~QtStraightConnection()
 {
 }
 
-QPainterPath QtStraightConnection::shape() const
+void QtStraightConnection::setColor(QColor color)
 {
-	QPainterPath path;
-	QLineF l = line();
-	QLineF n = l.normalVector();
-	n.setLength(5.0f);
+	QPen p = this->pen();
+	p.setColor(color);
+	this->setPen(p);
 
-	qreal x = n.x2() - n.x1();
-	qreal y = n.y2() - n.y1();
-
-	path.moveTo(l.x1() + x, l.y1() + y);
-	path.lineTo(l.x2() + x, l.y2() + y);
-	path.lineTo(l.x2() - x, l.y2() - y);
-	path.lineTo(l.x1() - x, l.y1() - y);
-	path.closeSubpath();
-
-	return path;
+	p = m_circle->pen();
+	p.setColor(color);
+	m_circle->setPen(p);
 }
 
-
 QtCorneredConnection::QtCorneredConnection(
 	Vec4i ownerRect, Vec4i targetRect, Vec4i ownerParentRect, Vec4i targetParentRect, QGraphicsItem* parent
 )
@@ -323,7 +341,7 @@ QtGraphEdge::QtGraphEdge(const std::weak_ptr<GraphNode>& owner, const std::weak_
 	, m_mouseMoved(false)
 {
 	this->setAcceptHoverEvents(true);
-	this->setZValue(1); // Used to draw edges always on top of nodes.
+	this->setZValue(getZValue(false)); // Used to draw edges always on top of nodes.
 
 	this->updateLine();
 }
@@ -358,11 +376,19 @@ void QtGraphEdge::updateLine()
 		delete m_child;
 	}
 
-	m_child = new QtCorneredConnection(
-		owner->getBoundingRect(), target->getBoundingRect(),
-		owner->getParentBoundingRect(), target->getParentBoundingRect(),
-		this
-	);
+	if (isAggregation())
+	{
+		m_child =
+			new QtStraightConnection(owner->getBoundingRect(), target->getBoundingRect(), getAggregationCount(), this);
+	}
+	else
+	{
+		m_child = new QtCorneredConnection(
+			owner->getBoundingRect(), target->getBoundingRect(),
+			owner->getParentBoundingRect(), target->getParentBoundingRect(),
+			this
+		);
+	}
 
 	QColor color;
 
@@ -377,12 +403,17 @@ void QtGraphEdge::updateLine()
 	case Edge::EDGE_INHERITANCE:
 		color = QColor("#CC5E89");
 		break;
+	case Edge::EDGE_AGGREGATION:
+		color = QColor("#F8F8F8");
+		break;
 	default:
 		color = QColor("#878787");
 		break;
 	}
 
-	m_child->setPen(QPen(color, 1));
+	m_child->setPen(QPen(color, getPenWidth()));
+
+	setIsActive(m_isActive);
 }
 
 bool QtGraphEdge::getIsActive() const
@@ -394,23 +425,47 @@ void QtGraphEdge::setIsActive(bool isActive)
 {
 	m_isActive = isActive;
 
-	QPen p = m_child->pen();
 	if (isActive)
 	{
-		p.setWidth(2);
-		this->setZValue(5);
+		if (isAggregation())
+		{
+			dynamic_cast<QtStraightConnection*>(m_child)->setColor(QColor("#EEE"));
+		}
+		else
+		{
+			QPen p = m_child->pen();
+			p.setWidth(getPenWidth() + 1);
+			m_child->setPen(p);
+		}
+		this->setZValue(getZValue(isActive));
 	}
 	else
 	{
-		p.setWidth(1);
-		this->setZValue(1);
+		if (isAggregation())
+		{
+			dynamic_cast<QtStraightConnection*>(m_child)->setColor(QColor("#F8F8F8"));
+		}
+		else
+		{
+			QPen p = m_child->pen();
+			p.setWidth(getPenWidth());
+			m_child->setPen(p);
+		}
+		this->setZValue(getZValue(isActive));
 	}
-	m_child->setPen(p);
 }
 
 void QtGraphEdge::onClick()
 {
-	MessageActivateToken(getData()->getId()).dispatch();
+	if (isAggregation())
+	{
+		const std::set<Id>& ids = getData()->getComponent<TokenComponentAggregation>()->getAggregationIds();
+		MessageActivateTokens(std::vector<Id>(ids.begin(), ids.end())).dispatch();
+	}
+	else
+	{
+		MessageActivateToken(getData()->getId()).dispatch();
+	}
 }
 
 void QtGraphEdge::mousePressEvent(QGraphicsSceneMouseEvent* event)
@@ -448,3 +503,44 @@ void QtGraphEdge::hoverLeaveEvent(QGraphicsSceneHoverEvent* event)
 {
 	this->setIsActive(m_isActive);
 }
+
+bool QtGraphEdge::isAggregation() const
+{
+	return getData()->getType() == Edge::EDGE_AGGREGATION;
+}
+
+int QtGraphEdge::getZValue(bool active) const
+{
+	if (isAggregation())
+	{
+		if (active)
+		{
+			return -1;
+		}
+		return -5;
+	}
+
+	if (active)
+	{
+		return 5;
+	}
+	return 1;
+}
+
+int QtGraphEdge::getPenWidth() const
+{
+	if (isAggregation())
+	{
+		return getAggregationCount() + 1;
+	}
+	return 1;
+}
+
+int QtGraphEdge::getAggregationCount() const
+{
+	if (isAggregation())
+	{
+		return getData()->getComponent<TokenComponentAggregation>()->getAggregationCount();
+	}
+	return 0;
+}
diff --git a/src/app/qt/view/graphElements/QtGraphEdge.h b/src/app/qt/view/graphElements/QtGraphEdge.h
index 6091d69c..ddafab30 100644
--- a/src/app/qt/view/graphElements/QtGraphEdge.h
+++ b/src/app/qt/view/graphElements/QtGraphEdge.h
@@ -6,20 +6,24 @@
 #include <QGraphicsItem>
 
 #include "utility/math/Vector2.h"
-#include "utility/messaging/type/MessageActivateToken.h"
 
 #include "component/view/graphElements/GraphEdge.h"
 
 class GraphNode;
+class QtGraphicsRoundedRectItem;
 
 class QtStraightConnection
 	: public QGraphicsLineItem
 {
 public:
-	QtStraightConnection(Vec4i ownerRect, Vec4i targetRect, QGraphicsItem* parent);
+	QtStraightConnection(Vec4i ownerRect, Vec4i targetRect, int number, QGraphicsItem* parent);
 	virtual ~QtStraightConnection();
 
-	virtual QPainterPath shape() const;
+	void setColor(QColor color);
+
+private:
+	QtGraphicsRoundedRectItem* m_circle;
+	QGraphicsSimpleTextItem* m_number;
 };
 
 class QtCorneredConnection
@@ -71,6 +75,11 @@ protected:
 	virtual void hoverLeaveEvent(QGraphicsSceneHoverEvent* event);
 
 private:
+	bool isAggregation() const;
+	int getZValue(bool active) const;
+	int getPenWidth() const;
+	int getAggregationCount() const;
+
 	std::weak_ptr<GraphNode> m_owner;
 	std::weak_ptr<GraphNode> m_target;
 
diff --git a/src/app/qt/view/graphElements/QtGraphNode.cpp b/src/app/qt/view/graphElements/QtGraphNode.cpp
index 8420007f..4a2fd615 100644
--- a/src/app/qt/view/graphElements/QtGraphNode.cpp
+++ b/src/app/qt/view/graphElements/QtGraphNode.cpp
@@ -161,14 +161,14 @@ Vec4i QtGraphNode::getParentBoundingRect() const
 
 bool QtGraphNode::addOutEdge(const std::shared_ptr<GraphEdge>& edge)
 {
-	for (std::list<std::shared_ptr<GraphEdge>>::iterator it = m_outEdges.begin(); it != m_outEdges.end(); it++)
-	{
-		if ((*it)->getOwner().lock() == edge->getOwner().lock() &&
-			(*it)->getTarget().lock() == edge->getTarget().lock())
-		{
-			return false;
-		}
-	}
+	// for (std::list<std::shared_ptr<GraphEdge>>::iterator it = m_outEdges.begin(); it != m_outEdges.end(); it++)
+	// {
+	// 	if ((*it)->getOwner().lock() == edge->getOwner().lock() &&
+	// 		(*it)->getTarget().lock() == edge->getTarget().lock())
+	// 	{
+	// 		return false;
+	// 	}
+	// }
 
 	m_outEdges.push_back(edge);
 	return true;
@@ -176,18 +176,18 @@ bool QtGraphNode::addOutEdge(const std::shared_ptr<GraphEdge>& edge)
 
 bool QtGraphNode::addInEdge(const std::weak_ptr<GraphEdge>& edge)
 {
-	for (std::list<std::weak_ptr<GraphEdge>>::iterator it = m_inEdges.begin(); it != m_inEdges.end(); it++)
-	{
-		std::shared_ptr<GraphEdge> existingEdge = it->lock();
-		if (existingEdge != NULL)
-		{
-			if (existingEdge->getOwner().lock() == edge.lock()->getOwner().lock() &&
-				existingEdge->getTarget().lock() == edge.lock()->getTarget().lock())
-			{
-				return false;
-			}
-		}
-	}
+	// for (std::list<std::weak_ptr<GraphEdge>>::iterator it = m_inEdges.begin(); it != m_inEdges.end(); it++)
+	// {
+	// 	std::shared_ptr<GraphEdge> existingEdge = it->lock();
+	// 	if (existingEdge != NULL)
+	// 	{
+	// 		if (existingEdge->getOwner().lock() == edge.lock()->getOwner().lock() &&
+	// 			existingEdge->getTarget().lock() == edge.lock()->getTarget().lock())
+	// 		{
+	// 			return false;
+	// 		}
+	// 	}
+	// }
 
 	m_inEdges.push_back(edge);
 	return true;
@@ -258,7 +258,7 @@ void QtGraphNode::setStyle()
 	QPen p(Qt::transparent);
 	QFont font(getFontForNodeType(m_data->getType()));
 
-	bool undefined = false;
+	bool useUndefinedPattern = false;
 	bool useUndefinedColor = false;
 
 	Vec2i padding;
@@ -266,9 +266,9 @@ void QtGraphNode::setStyle()
 	switch (m_data->getType())
 	{
 	case Node::NODE_UNDEFINED:
-		undefined = true;
+		p.setStyle(Qt::DashLine);
 	case Node::NODE_NAMESPACE:
-		color = Qt::white;
+		color = Qt::transparent;
 
 		p.setColor("#cc8d91");
 		p.setWidth(1);
@@ -279,7 +279,7 @@ void QtGraphNode::setStyle()
 		break;
 
 	case Node::NODE_UNDEFINED_TYPE:
-		undefined = true;
+		useUndefinedPattern = true;
 	case Node::NODE_STRUCT:
 	case Node::NODE_CLASS:
 	case Node::NODE_ENUM:
@@ -315,7 +315,7 @@ void QtGraphNode::setStyle()
 		break;
 
 	case Node::NODE_UNDEFINED_FUNCTION:
-		undefined = true;
+		useUndefinedPattern = true;
 		useUndefinedColor = true;
 	case Node::NODE_FUNCTION:
 	case Node::NODE_METHOD:
@@ -335,7 +335,7 @@ void QtGraphNode::setStyle()
 		break;
 
 	case Node::NODE_UNDEFINED_VARIABLE:
-		undefined = true;
+		useUndefinedPattern = true;
 		useUndefinedColor = true;
 	case Node::NODE_GLOBAL_VARIABLE:
 	case Node::NODE_FIELD:
@@ -365,7 +365,7 @@ void QtGraphNode::setStyle()
 	m_rect->setBrush(QBrush(color));
 	m_rect->setRadius(radius);
 
-	if (undefined)
+	if (useUndefinedPattern)
 	{
 		QtDeviceScaledPixmap pixmap("data/gui/graph_view/images/pattern.png");
 		pixmap.scaleToHeight(10);
diff --git a/src/lib/CMakeLists.txt b/src/lib/CMakeLists.txt
index e48cd8e3..f30f0f4f 100644
--- a/src/lib/CMakeLists.txt
+++ b/src/lib/CMakeLists.txt
@@ -87,6 +87,8 @@ add_files(
 	data/graph/token_component/TokenComponentAbstraction.h
 	data/graph/token_component/TokenComponentAccess.cpp
 	data/graph/token_component/TokenComponentAccess.h
+	data/graph/token_component/TokenComponentAggregation.cpp
+	data/graph/token_component/TokenComponentAggregation.h
 	data/graph/token_component/TokenComponentConst.cpp
 	data/graph/token_component/TokenComponentConst.h
 	data/graph/token_component/TokenComponentName.cpp
diff --git a/src/lib/component/controller/GraphController.cpp b/src/lib/component/controller/GraphController.cpp
index 0e5d0fd3..106d394c 100644
--- a/src/lib/component/controller/GraphController.cpp
+++ b/src/lib/component/controller/GraphController.cpp
@@ -168,7 +168,14 @@ DummyNode GraphController::createDummyNodeTopDown(Node* node)
 				return;
 			}
 
-			result.connected = true;
+			if (edge->isType(Edge::EDGE_AGGREGATION))
+			{
+				result.aggregated = true;
+			}
+			else
+			{
+				result.connected = true;
+			}
 
 			for (const DummyEdge& dummy : m_dummyEdges)
 			{
@@ -189,7 +196,7 @@ void GraphController::setActiveAndVisibility(const std::vector<Id>& activeTokenI
 {
 	for (DummyNode& node : m_dummyNodes)
 	{
-		setNodeActiveAndVisibilityRecursiveBottomUp(node, activeTokenIds);
+		setNodeActiveAndVisibilityRecursiveBottomUp(node, activeTokenIds, false);
 	}
 
 	for (DummyEdge& edge : m_dummyEdges)
@@ -203,7 +210,7 @@ void GraphController::setActiveAndVisibility(const std::vector<Id>& activeTokenI
 }
 
 bool GraphController::setNodeActiveAndVisibilityRecursiveBottomUp(
-	DummyNode& node, const std::vector<Id>& activeTokenIds
+	DummyNode& node, const std::vector<Id>& activeTokenIds, bool aggregated
 ) const {
 	node.visible = false;
 	node.active = false;
@@ -216,13 +223,13 @@ bool GraphController::setNodeActiveAndVisibilityRecursiveBottomUp(
 	bool childVisible = false;
 	for (DummyNode& subNode : node.subNodes)
 	{
-		if (setNodeActiveAndVisibilityRecursiveBottomUp(subNode, activeTokenIds))
+		if (setNodeActiveAndVisibilityRecursiveBottomUp(subNode, activeTokenIds, aggregated | node.aggregated))
 		{
 			childVisible = true;
 		}
 	}
 
-	if (node.active || node.connected || childVisible)
+	if (node.active || node.connected || childVisible || (!aggregated && node.aggregated))
 	{
 		setNodeVisibilityRecursiveTopDown(node);
 	}
diff --git a/src/lib/component/controller/GraphController.h b/src/lib/component/controller/GraphController.h
index 676a74cb..d1918b75 100644
--- a/src/lib/component/controller/GraphController.h
+++ b/src/lib/component/controller/GraphController.h
@@ -59,7 +59,8 @@ private:
 	DummyNode createDummyNodeTopDown(Node* node);
 
 	void setActiveAndVisibility(const std::vector<Id>& activeTokenIds);
-	bool setNodeActiveAndVisibilityRecursiveBottomUp(DummyNode& node, const std::vector<Id>& activeTokenIds) const;
+	bool setNodeActiveAndVisibilityRecursiveBottomUp(
+		DummyNode& node, const std::vector<Id>& activeTokenIds, bool aggregated) const;
 	void setNodeVisibilityRecursiveTopDown(DummyNode& node) const;
 
 	void layoutNesting();
diff --git a/src/lib/component/view/graphElements/GraphNode.h b/src/lib/component/view/graphElements/GraphNode.h
index 3f2ef26c..8e782f5d 100644
--- a/src/lib/component/view/graphElements/GraphNode.h
+++ b/src/lib/component/view/graphElements/GraphNode.h
@@ -52,6 +52,7 @@ struct DummyNode
 		, accessType(TokenComponentAccess::ACCESS_NONE)
 		, active(false)
 		, connected(false)
+		, aggregated(false)
 		, expanded(false)
 		, invisibleSubNodeCount(0)
 		, visible(false)
@@ -63,6 +64,7 @@ struct DummyNode
 		, accessType(accessType)
 		, active(false)
 		, connected(false)
+		, aggregated(false)
 		, expanded(false)
 		, invisibleSubNodeCount(0)
 		, visible(false)
@@ -77,6 +79,7 @@ struct DummyNode
 
 	bool active;
 	bool connected;
+	bool aggregated;
 
 	bool expanded;
 	size_t invisibleSubNodeCount;
diff --git a/src/lib/data/Storage.cpp b/src/lib/data/Storage.cpp
index 5e27e82a..1579976e 100644
--- a/src/lib/data/Storage.cpp
+++ b/src/lib/data/Storage.cpp
@@ -481,9 +481,16 @@ std::shared_ptr<Graph> Storage::getGraphForActiveTokenIds(const std::vector<Id>&
 			graph->addNodeAndAllChildrenAsPlainCopy(node->getLastParentNode());
 
 			node->forEachEdge(
-				[graph](Edge* edge)
+				[graph, node](Edge* edge)
 				{
-					graph->addEdgeAndAllChildrenAsPlainCopy(edge);
+					const Node::NodeTypeMask varFuncMask =
+						Node::NODE_UNDEFINED_FUNCTION | Node::NODE_FUNCTION | Node::NODE_METHOD |
+						Node::NODE_UNDEFINED_VARIABLE | Node::NODE_GLOBAL_VARIABLE | Node::NODE_FIELD;
+
+					if (!node->isType(varFuncMask) || !edge->isType(Edge::EDGE_AGGREGATION))
+					{
+						graph->addEdgeAndAllChildrenAsPlainCopy(edge);
+					}
 				}
 			);
 		}
diff --git a/src/lib/data/graph/Edge.cpp b/src/lib/data/graph/Edge.cpp
index 0cf2b5a0..22af22c7 100644
--- a/src/lib/data/graph/Edge.cpp
+++ b/src/lib/data/graph/Edge.cpp
@@ -3,6 +3,7 @@
 #include <sstream>
 
 #include "data/graph/Node.h"
+#include "data/graph/token_component/TokenComponentAggregation.h"
 #include "data/graph/token_component/TokenComponentAccess.h"
 #include "utility/logging/logging.h"
 
@@ -76,6 +77,22 @@ bool Edge::isEdge() const
 	return true;
 }
 
+void Edge::addComponentAggregation(std::shared_ptr<TokenComponentAggregation> component)
+{
+	if (getComponent<TokenComponentAggregation>())
+	{
+		LOG_ERROR("TokenComponentAggregation has been set before!");
+	}
+	else if (m_type != EDGE_AGGREGATION)
+	{
+		LOG_ERROR("TokenComponentAggregation can't be set on edge of type: " + getTypeString());
+	}
+	else
+	{
+		addComponent(component);
+	}
+}
+
 void Edge::addComponentAccess(std::shared_ptr<TokenComponentAccess> component)
 {
 	if (getComponent<TokenComponentAccess>())
@@ -118,6 +135,8 @@ std::string Edge::getTypeString(EdgeType type) const
 		return "template parameter";
 	case EDGE_TEMPLATE_SPECIALIZATION_OF:
 		return "template specialization";
+	case EDGE_AGGREGATION:
+		return "aggregation";
 	}
 	return "";
 }
@@ -132,10 +151,16 @@ std::string Edge::getAsString() const
 	std::stringstream str;
 	str << "[" << getId() << "] " << getTypeString() << ": \"" << m_from->getName() << "\" -> \"" + m_to->getName() << "\"";
 
-	TokenComponentAccess* component = getComponent<TokenComponentAccess>();
-	if (component)
+	TokenComponentAccess* access = getComponent<TokenComponentAccess>();
+	if (access)
 	{
-		str << " " << component->getAccessString();
+		str << " " << access->getAccessString();
+	}
+
+	TokenComponentAggregation* aggregation = getComponent<TokenComponentAggregation>();
+	if (aggregation)
+	{
+		str << " " << aggregation->getAggregationCount();
 	}
 
 	return str.str();
@@ -222,6 +247,13 @@ bool Edge::checkType() const
 			break;
 		}
 		return true;
+
+	case EDGE_AGGREGATION:
+		if (!m_from->isType(typeMask | variableMask | functionMask) || !m_to->isType(typeMask | variableMask | functionMask))
+		{
+			break;
+		}
+		return true;
 	}
 
 	LOG_ERROR_STREAM(
diff --git a/src/lib/data/graph/Edge.h b/src/lib/data/graph/Edge.h
index 34883d4a..c18174fc 100644
--- a/src/lib/data/graph/Edge.h
+++ b/src/lib/data/graph/Edge.h
@@ -7,6 +7,7 @@
 #include "data/graph/Token.h"
 
 class Node;
+class TokenComponentAggregation;
 class TokenComponentAccess;
 class TokenComponentDataType;
 
@@ -26,7 +27,9 @@ public:
 		EDGE_INHERITANCE				= 0x80,
 		EDGE_TYPEDEF_OF					= 0x100,
 		EDGE_TEMPLATE_PARAMETER_OF		= 0x200,
-		EDGE_TEMPLATE_SPECIALIZATION_OF	= 0x400
+		EDGE_TEMPLATE_SPECIALIZATION_OF	= 0x400,
+
+		EDGE_AGGREGATION				= 0x800
 	};
 
 	Edge(EdgeType type, Node* from, Node* to);
@@ -46,6 +49,7 @@ public:
 	virtual bool isEdge() const;
 
 	// Component setters
+	void addComponentAggregation(std::shared_ptr<TokenComponentAggregation> component);
 	void addComponentAccess(std::shared_ptr<TokenComponentAccess> component);
 
 	// Logging.
diff --git a/src/lib/data/graph/StorageGraph.cpp b/src/lib/data/graph/StorageGraph.cpp
index d43ba326..2ccb81d9 100644
--- a/src/lib/data/graph/StorageGraph.cpp
+++ b/src/lib/data/graph/StorageGraph.cpp
@@ -1,5 +1,6 @@
 #include "data/graph/StorageGraph.h"
 
+#include "data/graph/token_component/TokenComponentAggregation.h"
 #include "data/graph/token_component/TokenComponentName.h"
 #include "utility/logging/logging.h"
 #include "utility/utilityString.h"
@@ -87,7 +88,16 @@ Edge* StorageGraph::createEdge(Edge::EdgeType type, Node* from, Node* to)
 		return edge;
 	}
 
-	return insertEdge(type, from, to);
+	edge = insertEdge(type, from, to);
+
+	if (from->getLastParentNode() != to->getLastParentNode())
+	{
+		Id edgeId = edge->getId();
+		updateAggregationEdges(from->getParentNode(), to, edgeId);
+		updateAggregationEdges(from, to->getParentNode(), edgeId);
+	}
+
+	return edge;
 }
 
 Node* StorageGraph::insertNodeHierarchy(Node::NodeType type, SearchNode* searchNode)
@@ -140,3 +150,39 @@ Edge* StorageGraph::insertEdge(Edge::EdgeType type, Node* from, Node* to)
 	m_edges.emplace(edgePtr->getId(), edgePtr);
 	return edgePtr.get();
 }
+
+void StorageGraph::updateAggregationEdges(Node* from, Node* to, Id edgeId)
+{
+	if (!from || !to || from == to)
+	{
+		return;
+	}
+
+	const Node::NodeTypeMask mask = Node::NODE_UNDEFINED_TYPE | Node::NODE_CLASS | Node::NODE_STRUCT | Node::NODE_ENUM;
+	const Node::NodeTypeMask varFuncMask =
+		Node::NODE_UNDEFINED_FUNCTION | Node::NODE_FUNCTION | Node::NODE_UNDEFINED_VARIABLE | Node::NODE_GLOBAL_VARIABLE;
+
+	if ((from->isType(mask) && to->isType(mask | varFuncMask)) ||
+		(from->isType(mask | varFuncMask) && to->isType(mask)))
+	{
+		Edge* edge = from->findEdgeOfType(Edge::EDGE_AGGREGATION,
+			[from, to](Edge* e)
+			{
+				const Node* f = e->getFrom();
+				const Node* t = e->getTo();
+				return (f == from && t == to) || (f == to && t == from);
+			}
+		);
+
+		if (!edge)
+		{
+			edge = insertEdge(Edge::EDGE_AGGREGATION, from, to);
+			edge->addComponentAggregation(std::make_shared<TokenComponentAggregation>());
+		}
+
+		edge->getComponent<TokenComponentAggregation>()->addAggregationId(edgeId);
+	}
+
+	updateAggregationEdges(from->getParentNode(), to, edgeId);
+	updateAggregationEdges(from, to->getParentNode(), edgeId);
+}
diff --git a/src/lib/data/graph/StorageGraph.h b/src/lib/data/graph/StorageGraph.h
index f7915993..66dc1744 100644
--- a/src/lib/data/graph/StorageGraph.h
+++ b/src/lib/data/graph/StorageGraph.h
@@ -21,6 +21,8 @@ private:
 	Node* insertNodeHierarchy(Node::NodeType type, SearchNode* searchNode);
 	Node* insertNode(Node::NodeType type, Node* parentNode, SearchNode* searchNode);
 	Edge* insertEdge(Edge::EdgeType type, Node* from, Node* to);
+
+	void updateAggregationEdges(Node* from, Node* to, Id edgeId);
 };
 
 #endif // STORAGE_GRAPH_H
diff --git a/src/lib/data/graph/token_component/TokenComponentAggregation.cpp b/src/lib/data/graph/token_component/TokenComponentAggregation.cpp
new file mode 100644
index 00000000..5110d06d
--- /dev/null
+++ b/src/lib/data/graph/token_component/TokenComponentAggregation.cpp
@@ -0,0 +1,29 @@
+#include "data/graph/token_component/TokenComponentAggregation.h"
+
+TokenComponentAggregation::TokenComponentAggregation()
+{
+}
+
+TokenComponentAggregation::~TokenComponentAggregation()
+{
+}
+
+std::shared_ptr<TokenComponent> TokenComponentAggregation::copy() const
+{
+	return std::make_shared<TokenComponentAggregation>(*this);
+}
+
+int TokenComponentAggregation::getAggregationCount() const
+{
+	return m_ids.size();
+}
+
+void TokenComponentAggregation::addAggregationId(Id id)
+{
+	m_ids.insert(id);
+}
+
+const std::set<Id>& TokenComponentAggregation::getAggregationIds() const
+{
+	return m_ids;
+}
diff --git a/src/lib/data/graph/token_component/TokenComponentAggregation.h b/src/lib/data/graph/token_component/TokenComponentAggregation.h
new file mode 100644
index 00000000..c384994e
--- /dev/null
+++ b/src/lib/data/graph/token_component/TokenComponentAggregation.h
@@ -0,0 +1,27 @@
+#ifndef TOKEN_COMPONENT_AGGREGATION_H
+#define TOKEN_COMPONENT_AGGREGATION_H
+
+#include <set>
+
+#include "utility/types.h"
+
+#include "data/graph/token_component/TokenComponent.h"
+
+class TokenComponentAggregation
+	: public TokenComponent
+{
+public:
+	TokenComponentAggregation();
+	virtual ~TokenComponentAggregation();
+
+	virtual std::shared_ptr<TokenComponent> copy() const;
+
+	int getAggregationCount() const;
+	void addAggregationId(Id id);
+	const std::set<Id>& getAggregationIds() const;
+
+private:
+	std::set<Id> m_ids;
+};
+
+#endif // TOKEN_COMPONENT_AGGREGATION_H
diff --git a/src/lib/utility/math/VectorBase.h b/src/lib/utility/math/VectorBase.h
index 71927ec4..98e5dcfe 100644
--- a/src/lib/utility/math/VectorBase.h
+++ b/src/lib/utility/math/VectorBase.h
@@ -39,11 +39,11 @@ public:
 	void assign(const VectorBase<U, N>& other);
 
 	template<class U>
-	VectorBase<T, N> add(const VectorBase<U, N>& other);
+	VectorBase<T, N>& add(const VectorBase<U, N>& other);
 	template<class U>
-	VectorBase<T, N> subtract(const VectorBase<U, N>& other);
+	VectorBase<T, N>& subtract(const VectorBase<U, N>& other);
 	template<class U>
-	VectorBase<T, N> scalarMultiplication(const U& scalar);
+	VectorBase<T, N>& scalarMultiplication(const U& scalar);
 	template<class U>
 	T dotProduct(const VectorBase<U, N>& other);
 
@@ -71,13 +71,13 @@ public:
 	VectorBase<T, N> operator/(const U& scalar) const;
 
 	template<class U>
-	VectorBase<T, N> operator+=(const VectorBase<U, N>& other);
+	VectorBase<T, N>& operator+=(const VectorBase<U, N>& other);
 	template<class U>
-	VectorBase<T, N> operator-=(const VectorBase<U, N>& other);
+	VectorBase<T, N>& operator-=(const VectorBase<U, N>& other);
 	template<class U>
-	VectorBase<T, N> operator*=(const U& scalar);
+	VectorBase<T, N>& operator*=(const U& scalar);
 	template<class U>
-	VectorBase<T, N> operator/=(const U& scalar);
+	VectorBase<T, N>& operator/=(const U& scalar);
 
 	// Checks whether all values are the same.
 	template<class U>
@@ -238,7 +238,7 @@ void VectorBase<T, N>::assign(const VectorBase<U, N>& other)
 
 template<class T, unsigned int N>
 template<class U>
-VectorBase<T, N> VectorBase<T, N>::add(const VectorBase<U, N>& other)
+VectorBase<T, N>& VectorBase<T, N>::add(const VectorBase<U, N>& other)
 {
 	T tmpValues[N];
 	for (unsigned int i = 0; i < N; i++)
@@ -253,7 +253,7 @@ VectorBase<T, N> VectorBase<T, N>::add(const VectorBase<U, N>& other)
 
 template<class T, unsigned int N>
 template<class U>
-VectorBase<T, N> VectorBase<T, N>::subtract(const VectorBase<U, N>& other)
+VectorBase<T, N>& VectorBase<T, N>::subtract(const VectorBase<U, N>& other)
 {
 	T tmpValues[N];
 	for (unsigned int i = 0; i < N; i++)
@@ -268,7 +268,7 @@ VectorBase<T, N> VectorBase<T, N>::subtract(const VectorBase<U, N>& other)
 
 template<class T, unsigned int N>
 template<class U>
-VectorBase<T, N> VectorBase<T, N>::scalarMultiplication(const U& scalar)
+VectorBase<T, N>& VectorBase<T, N>::scalarMultiplication(const U& scalar)
 {
 	T tmpValues[N];
 	for (unsigned int i = 0; i < N; i++)
@@ -371,28 +371,28 @@ VectorBase<T, N> VectorBase<T, N>::operator/(const U& scalar) const
 
 template<class T, unsigned int N>
 template<class U>
-VectorBase<T, N> VectorBase<T, N>::operator+=(const VectorBase<U, N>& other)
+VectorBase<T, N>& VectorBase<T, N>::operator+=(const VectorBase<U, N>& other)
 {
 	return add(other);
 }
 
 template<class T, unsigned int N>
 template<class U>
-VectorBase<T, N> VectorBase<T, N>::operator-=(const VectorBase<U, N>& other)
+VectorBase<T, N>& VectorBase<T, N>::operator-=(const VectorBase<U, N>& other)
 {
 	return subtract(other);
 }
 
 template<class T, unsigned int N>
 template<class U>
-VectorBase<T, N> VectorBase<T, N>::operator*=(const U& scalar)
+VectorBase<T, N>& VectorBase<T, N>::operator*=(const U& scalar)
 {
 	return scalarMultiplication(scalar);
 }
 
 template<class T, unsigned int N>
 template<class U>
-VectorBase<T, N> VectorBase<T, N>::operator/=(const U& scalar)
+VectorBase<T, N>& VectorBase<T, N>::operator/=(const U& scalar)
 {
 	return scalarMultiplication(1.0f / scalar);
 }
diff --git a/src/test/GraphFilterConductorTestSuite.h b/src/test/GraphFilterConductorTestSuite.h
index 6aa93969..4e6a6f6d 100644
--- a/src/test/GraphFilterConductorTestSuite.h
+++ b/src/test/GraphFilterConductorTestSuite.h
@@ -99,9 +99,10 @@ public:
 			"7 nodes: "
 				"class:A field:A::count undefined_type:int undefined_type:void class:B function:main "
 				"undefined_function:B::B\n"
-			"7 edges: "
-				"child:A->A::count type_use:A::count->int inheritance:B->A return_type:main->int type_usage:main->B "
-				"child:B->B::B call:main->B::B\n"
+			"13 edges: "
+				"child:A->A::count aggregation:A->int aggregation:A->void type_use:A::count->int inheritance:B->A "
+				"aggregation:B->void aggregation:B->int return_type:main->int type_usage:main->B child:B->B::B "
+				"call:main->B::B aggregation:main->B aggregation:main->A\n"
 		);
 	}
 
diff --git a/src/test/StorageGraphTestSuite.h b/src/test/StorageGraphTestSuite.h
index 0b6c7751..9e872fc3 100644
--- a/src/test/StorageGraphTestSuite.h
+++ b/src/test/StorageGraphTestSuite.h
@@ -1,5 +1,6 @@
 #include "cxxtest/TestSuite.h"
 
+#include "data/graph/token_component/TokenComponentAggregation.h"
 #include "data/graph/StorageGraph.h"
 #include "data/search/SearchIndex.h"
 
@@ -74,6 +75,32 @@ public:
 		TS_ASSERT_EQUALS(ab->getParentNode(), a);
 	}
 
+	void test_graph_creates_aggregation_edges()
+	{
+		TestStorageGraph graph;
+		Node* a = graph.createNodeHierarchy(Node::NODE_CLASS, "A");
+		Node* ab = graph.createNodeHierarchy(Node::NODE_CLASS, "A::B");
+		Node* c = graph.createNodeHierarchy(Node::NODE_CLASS, "C");
+		Node* cd = graph.createNodeHierarchy(Node::NODE_CLASS, "C::D");
+		Node* cdd = graph.createNodeHierarchy(Node::NODE_METHOD, "C::D::D");
+		Edge* i = graph.createEdge(Edge::EDGE_INHERITANCE, ab, cd);
+		Edge* t = graph.createEdge(Edge::EDGE_TYPE_USAGE, cdd, a);
+
+		TS_ASSERT_EQUALS(5, graph.getNodeCount());
+		TS_ASSERT_EQUALS(8, graph.getEdgeCount());
+
+		Edge* e1 = graph.getEdge(Edge::EDGE_AGGREGATION, a, c);
+		TS_ASSERT(e1);
+		TS_ASSERT_EQUALS(2, e1->getComponent<TokenComponentAggregation>()->getAggregationCount());
+		TS_ASSERT_EQUALS(i->getId(), *e1->getComponent<TokenComponentAggregation>()->getAggregationIds().begin());
+		TS_ASSERT_EQUALS(t->getId(), *(++e1->getComponent<TokenComponentAggregation>()->getAggregationIds().begin()));
+
+		Edge* e2 = graph.getEdge(Edge::EDGE_AGGREGATION, ab, c);
+		TS_ASSERT(e2);
+		TS_ASSERT_EQUALS(1, e2->getComponent<TokenComponentAggregation>()->getAggregationCount());
+		TS_ASSERT_EQUALS(i->getId(), *e2->getComponent<TokenComponentAggregation>()->getAggregationIds().begin());
+	}
+
 	void test_graph_removes_nodes()
 	{
 		TestStorageGraph graph;
@@ -278,14 +305,14 @@ public:
 			}
 		);
 
-		TS_ASSERT_EQUALS(4, plainGraph.getNodeCount());
-		TS_ASSERT_EQUALS(3, plainGraph.getEdgeCount());
+		TS_ASSERT_EQUALS(5, plainGraph.getNodeCount());
+		TS_ASSERT_EQUALS(4, plainGraph.getEdgeCount());
 
 		TS_ASSERT(plainGraph.getNode("A"));
 		TS_ASSERT(plainGraph.getNode("A::B"));
 		TS_ASSERT(plainGraph.getNode("A::B::C"));
 		TS_ASSERT(plainGraph.getNode("D"));
-		TS_ASSERT(!plainGraph.getNode("E"));
+		TS_ASSERT(plainGraph.getNode("E"));
 	}
 
 private: