Hi, Below is code for doing a boolean OR operation. I'm not sure of the mistake I'm doing here. The output generated is wrong. I'm not using the operator+() becaue of the compile issue on MSVC2010. #include <boost/polygon/polygon.hpp> namespace gtl = boost::polygon; using namespace gtl; using namespace boost::polygon::operators; using namespace std; typedef gtl::polygon_set_data<double> CPolygonSet; typedef gtl::polygon_data<double> CPolygon; static void test_boost_polygons() { CPolygonSet polyset1, polyset2, rset; CPolygon polygon1, polygon2; typedef gtl::polygon_traits<CPolygon>::point_type CPoint; vector<CPoint> poly1Points, poly2Points; poly1Points.push_back(gtl::construct<CPoint>(0.0000, 0.0000)); poly1Points.push_back(gtl::construct<CPoint>(50.0000, 50.0000)); poly1Points.push_back(gtl::construct<CPoint>(100.0000, -50.0000)); poly1Points.push_back(gtl::construct<CPoint>(50.0000, -50.0000)); poly2Points.push_back(gtl::construct<CPoint>(50.0000, 0.0000)); poly2Points.push_back(gtl::construct<CPoint>(100.0000, 50.0000)); poly2Points.push_back(gtl::construct<CPoint>(150.0000, -50.0000)); polygon1.set(poly1Points.begin(), poly1Points.end()); polygon2.set(poly2Points.begin(), poly2Points.end()); vector<CPolygon> polygonArray1, polygonArray2; polygonArray1.push_back(polygon1); polygonArray2.push_back(polygon2); polyset1.insert(polygonArray1.begin(), polygonArray1.end()); polyset2.insert(polygonArray2.begin(), polygonArray2.end()); gtl::arbitrary_boolean_op<CPolygonSet::coordinate_type> bop; bop.execute(rset, polyset1.begin(), polyset1.end(), polyset2.begin(), polyset2.end(), 0); vector<CPolygon> polys; rset.get(polys); for(unsigned int i = 0; i < polys.size(); ++i) { CPolygon::iterator_type it = polys[i].begin(); for(; it != polys[i].end(); ++it) { cout<<"("<<(*it).x()<<", "<<(*it).y()<<")"<<endl; } } } void main() { test_boost_polygons(); } -- -praveen