Hi, I am trying to perform serialization on a const member const ImageRegion* imageRegion; By refering to http://www.boost.org/libs/serialization/doc/serialization.html#const, I thought the following code would work. friend class boost::serialization::access; template<class Archive> void serialize(Archive & ar, const unsigned int version) { ar & const_cast<ImageRegion *>(imageRegion); } However, I still get the following error is VC++ 2003 c:\yccheok\pcbvisionlib\FiducialPair.h(42): error C2679: binary '&' : no operator found which takes a right-hand operand of type 'ImageRegion *' (or there is no acceptable conversion) I had fully tested the ImageRegion class. Before this const member variable, it can be fully serialized with no problem. Any suggestion? Thank you! p/s By refering to the mailing list "(de)serializing vector<const A*>" http://groups.google.com/group/boost-list/browse_frm/thread/79dba906901d039f/38ac71e4da0c1b3d?lnk=gst&q=serialization+const+pointer&rnum=7#38ac71e4da0c1b3d, does it mean that boost is also not allow to (de)serialize map<const CLASS*, CLASS> directly? Must I iterate through the map elements one by one to serialize them manually? __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com