I just submitted a patch (http://scipy.org/scipy/scipy/ticket/743) extending the functionality of io.matlab for v5 files, adding writers for structs, cell arrays, & objects, and readers+writers for function handles and 64-bit ints. The patch modifies the numpy types of strings, structs, and objects loaded from matlab: matlab strings are loaded as numpy arrays of unicode strings, rather than numpy arrays of objects. structs are loaded as numpy arrays with dtype [(field_name, object), ...] matlab objects are wrapped in an mio5.MatlabObject instance, which contains a 1x1 struct & the object classname. (function handles are also wrapped in a special object in mio5.py) These changes were to make the scipy<->matlab mapping more explicit. The changes to the string type probably don't break any existing code. The changes to the struct & matlab objects probably do. It's possible to make both of these backward compatible, if that's a priority. We're looking for feedback on that (or any other) issue. Ray Jones