diff --git a/src/barchart/barchartseries.cpp b/src/barchart/barchartseries.cpp
index 97b0ce5..a5011da 100644
--- a/src/barchart/barchartseries.cpp
+++ b/src/barchart/barchartseries.cpp
@@ -20,13 +20,11 @@ int BarChartSeries::min()
 
     // TODO: make min and max members and update them when data changes.
     // This is slower since they are checked every time, even if data is same since previous call.
-    QModelIndex modelIndex = mModel->index(0,0);
-    int min = mModel->data(modelIndex).toInt();
+    int min = INT_MAX;
 
     for (int i=0; i <mModel->rowCount(); i++) {
         for(int j=0; j<mModel->columnCount(); j++) {
-            modelIndex = mModel->index(i,j);
-            int temp = mModel->data(modelIndex).toInt();
+            int temp = mModel->data(mModel->index(i,j)).toInt();
             if (temp < min) {
                 min = temp;
             }
@@ -42,13 +40,11 @@ int BarChartSeries::max()
 
     // TODO: make min and max members and update them when data changes.
     // This is slower since they are checked every time, even if data is same since previous call.
-    QModelIndex modelIndex = mModel->index(0,0);
-    int max = mModel->data(modelIndex).toInt();
+    int max = INT_MIN;
 
     for (int i=0; i <mModel->rowCount(); i++) {
         for(int j=0; j<mModel->columnCount(); j++) {
-            modelIndex = mModel->index(i,j);
-            int temp = mModel->data(modelIndex).toInt();
+            int temp = mModel->data(mModel->index(i,j)).toInt();
             if (temp > max) {
                 max = temp;
             }
@@ -63,7 +59,7 @@ int BarChartSeries::countSeries()
     return mModel->rowCount();
 }
 
-int BarChartSeries::countItemsInSeries()
+int BarChartSeries::countColumns()
 {
     return mModel->columnCount();
 }
@@ -73,19 +69,11 @@ int BarChartSeries::countTotalItems()
     return mModel->rowCount() * mModel->columnCount();
 }
 
-int BarChartSeries::valueAt(int series, int item)
+int BarChartSeries::valueAt(int row, int column)
 {
-    QModelIndex index = mModel->index(series,item);
-    return mModel->data(index).toInt();
+    return mModel->data(mModel->index(row,column)).toInt();
 }
 
-/*
-void BarChartSeries::chartSizeChanged(QRectF rect)
-{
-    qDebug() << "barchart size changed:" << rect;
-//    mBarGroup->resize(rect.toRect().width(), rect.toRect().height());
-}
-*/
 #include "moc_barchartseries.cpp"
 
 QTCOMMERCIALCHART_END_NAMESPACE
diff --git a/src/barchart/barchartseries.h b/src/barchart/barchartseries.h
index 42a97e4..6ca8d7d 100644
--- a/src/barchart/barchartseries.h
+++ b/src/barchart/barchartseries.h
@@ -2,7 +2,7 @@
 #define BARCHARTSERIES_H
 
 #include <QList>
-#include <QRectF>
+//#include <QRectF>
 #include <QAbstractItemModel>
 #include "qchartseries.h"
 #include "qchartglobal.h"
@@ -29,9 +29,9 @@ public:
     int min();
     int max();
     int countSeries();
-    int countItemsInSeries();     // Count items in one series.
+    int countColumns();     // Count items in one series.
     int countTotalItems();
-    int valueAt(int series, int item);
+    int valueAt(int row, int column);
 
 public Q_SLOTS:
 
diff --git a/src/barchart/bargroup.cpp b/src/barchart/bargroup.cpp
index 88eab42..7d191f3 100644
--- a/src/barchart/bargroup.cpp
+++ b/src/barchart/bargroup.cpp
@@ -4,12 +4,6 @@
 
 QTCOMMERCIALCHART_BEGIN_NAMESPACE
 
-// TODO: singleton?
-//BarGroup* BarGroup::mBarGroupInstance = NULL;
-
-//BarGroup::BarGroup(QGraphicsItem *parent) :
-//    QGraphicsItem(parent)
-//    ,mSeries(series)
 BarGroup::BarGroup(BarChartSeries& series, QGraphicsItem *parent) :
   ChartItem(parent)
   ,mSeries(series)
@@ -107,7 +101,7 @@ void BarGroup::layoutChanged()
     }
 
     // TODO: better way to auto-layout
-    int count = mSeries.countItemsInSeries();
+    int count = mSeries.countColumns();
     int posStep = (mWidth / (count+1));
     int startPos = (mWidth / (count+1)) - mSeries.countSeries() * mBarDefaultWidth /2;
     qDebug() << "startpos" << startPos;
@@ -115,7 +109,7 @@ void BarGroup::layoutChanged()
     // Scaling.
     int itemIndex(0);
     for (int series = 0; series < mSeries.countSeries(); series++) {
-        for (int item=0; item < mSeries.countItemsInSeries(); item++) {
+        for (int item=0; item < mSeries.countColumns(); item++) {
             qDebug() << itemIndex;
             int barHeight = mSeries.valueAt(series, item) * mHeight / mMax;
             Bar* bar = reinterpret_cast<Bar*> (childItems().at(itemIndex));
diff --git a/src/barchart/bargroup.h b/src/barchart/bargroup.h
index 808ad8f..f630c7a 100644
--- a/src/barchart/bargroup.h
+++ b/src/barchart/bargroup.h
@@ -1,5 +1,5 @@
-#ifndef QBARCHART_H
-#define QBARCHART_H
+#ifndef QBARGROUP_H
+#define QBARGROUP_H
 
 #include "chartitem_p.h"
 #include "bar.h"
@@ -7,25 +7,8 @@
 
 QTCOMMERCIALCHART_BEGIN_NAMESPACE
 
-// TODO: Better name for this? The function of this class is to know where each bar in series is laid out.
-//class BarGroup : public QGraphicsItemGroup
-
 class BarGroup : public ChartItem
 {
-/* // TODO: implement as singleton?
-private:
-    static BarGroup* mBarGroupInstance;
-
-public:
-    static BarGroup* instance()
-    {
-        if (mBarGroupInstance == NULL) {
-            mBarGroupInstance = new BarGroup();
-        }
-        return mBarGroupInstance;
-    }
-private:
-*/
 public:
     explicit BarGroup(BarChartSeries& series, QGraphicsItem *parent = 0);
 
@@ -68,4 +51,4 @@ private:
 
 QTCOMMERCIALCHART_END_NAMESPACE
 
-#endif // QBARCHART_H
+#endif // QBARGROUP_H
diff --git a/src/qchartseries.h b/src/qchartseries.h
index 86d033c..9677140 100644
--- a/src/qchartseries.h
+++ b/src/qchartseries.h
@@ -15,6 +15,7 @@ public:
         SeriesTypeLine = 0,
 //        SeriesTypeArea,
         SeriesTypeBar,
+        SeriesTypeStackedBar,
         SeriesTypePie,
         SeriesTypeScatter
 //        SeriesTypeSpline
diff --git a/src/src.pro b/src/src.pro
index 302527b..0345e1c 100644
--- a/src/src.pro
+++ b/src/src.pro
@@ -26,7 +26,9 @@ SOURCES += \
     pieslice.cpp \
     qchartview.cpp \
     qchartseries.cpp \
-    qchartaxis.cpp
+    qchartaxis.cpp \
+    barchart/stackedbarchartseries.cpp \
+    barchart/stackedbargroup.cpp
 
 PRIVATE_HEADERS += \ 
     xylinechart/xylinechartitem_p.h \
@@ -49,7 +51,9 @@ PUBLIC_HEADERS += \
     qchartview.h \
     qchartaxis.h 
    
-HEADERS += $$PUBLIC_HEADERS
+HEADERS += $$PUBLIC_HEADERS \
+    barchart/stackedbarchartseries.h \
+    barchart/stackedbargroup.h
 HEADERS += $$PRIVATE_HEADERS
 
 INCLUDEPATH += xylinechart \