I think this is related to the similar problem just discussed in connection with Boost.Unordered with the same compiler. The following struct employee { employee(int id_,std::string name_,int age_,int ssn_); // ... }; employee_set es8({{0,"Rose",40,4512},{1,"Mary",38,3345}, {2,"Jo",25,7102}}); gives me (see http://tinyurl.com/pg4fsln ) ..\libs\multi_index\test\test_copy_assignment.cpp(159) : error C2440: 'initializing' : cannot convert from 'initializer-list' to 'boost::multi_index::multi_index_container<[...]>' No constructor could take the source type, or constructor overload resolution was ambiguous and this es9={{0,"Rose",40,4512},{1,"Mary",38,3345},{2,"Jo",25,7102}, {0,"Rose",40,4512}}; results in ..\libs\multi_index\test\test_copy_assignment.cpp(162) : error C2593: 'operator =' is ambiguous D:\teeks99-10\boost\boost/multi_index_container.hpp(329): could be 'boost::multi_index::multi_index_container<[...]> &boost::multi_index::multi_index_container<[...]>::operator= (std::initializer_list<employee>)' D:\teeks99-10\boost\boost/multi_index_container.hpp(321): or 'boost::multi_index::multi_index_container<[...]> &boost::multi_index::multi_index_container<[...]>::operator = (boost::multi_index::multi_index_container<[...]> &&)' D:\teeks99-10\boost\boost/multi_index_container.hpp(313): or 'boost::multi_index::multi_index_container<[...]> &boost::multi_index::multi_index_container<[...]>::operator = (const boost::multi_index::multi_index_container<[...]> &)' while trying to match the argument list '(employee_set, initializer-list)' Is this the compiler's fault or mine? Any applicable library-side workarond? Thank you, Joaquín M López Muñoz Telefónica Digital