Hi, Please consider the following variation of the example in the tutorial. The main difference here is that the class that is being wrapped has a non-default destructor. Without a destructor declared in BaseWrap, this gives the error error: base `World' with only non-default constructor in class without a constructor Adding a default constructor to the wrapper class makes the error go away, eg. BaseWrap():Base(0){} I can't find an example of this anywhere. I've looked at the docs, but don't understand what is going on well enough. So, I'm asking here. Is this Ok, and can I use any default constructor for the wrapper class without it making any difference? One other thing. Am I correct in thinking that wrapping the base class in this fashion is necessary if I want to wrap the derived classes? Clarifications appreciated. I'm not subscribed, so please cc me at faheem@email.unc.edu if possible. Thanks. Faheem. ************************************************************************* #include <boost/python.hpp> #include <boost/python/module.hpp> #include <boost/python/class.hpp> #include <boost/python/return_value_policy.hpp> #include <boost/python/manage_new_object.hpp> #include <boost/python/reference_existing_object.hpp> #include <boost/python/pure_virtual.hpp> #include <boost/python/wrapper.hpp> #include <boost/python/def.hpp> #include <boost/python/call.hpp> #include <boost/utility.hpp> #include <iostream> #include <string> using namespace boost::python; struct Base { int data; Base(int _data):data(_data){} virtual ~Base() {} virtual int f() = 0; }; struct BaseWrap : Base, wrapper<Base> { BaseWrap():Base(0){} int f() { return this->get_override("f")(); } }; BOOST_PYTHON_MODULE_INIT(polymorphism2_ext) { class_<BaseWrap, boost::noncopyable>("Base") .def("f", pure_virtual(&Base::f)) ; }