I am going through the tutorial for Statechart. Going through the section "adding reactions", while debug build links fine, in a release mode linker issues following complaints: 1>FSM.obj : error LNK2001: unresolved external symbol "public: void __thiscall boost::statechart::detail::no_context::no_function<struct EvReset>(struct EvReset const &)" (??$no_function@UEvReset@@@no_context@detail@statechart@boost@@QAEXABUEvReset@@@Z) 1>FSM.obj : error LNK2001: unresolved external symbol "public: void __thiscall boost::statechart::detail::no_context::no_function<struct EvStartStop>(struct EvStartStop const &)" (??$no_function@UEvStartStop@@@no_context@detail@statechart@boost@@QAEXABUEvStartStop@@@Z) I ended up adding following line to my cpp file: template< class Event > void sc::detail::no_context::no_function( const Event & ) {}; and it cured the linker complaint. Michael