The current version of chimera, that we make available for Mac OS X, does not work in stereo because Apple's X11 server does not support stereo. All of the code is in place, so if Apple ever does get X11 stereo working, chimera will work too. (Please consider filing a bug report with Apple if this affects you.) Consequently, I've resurected the Aqua version, which does work in stereo. There are still many bugs in the GUI toolkit that chimera uses (Tcl/Tk) for Aqua that we have not worked around yet, but it is usable if you have already used the normal version of chimera. The Aqua version is availble in the snapshot section of the chimera download web page, <http://www.cgl.ucsf.edu/chimera/download.html>. Greg Couch UCSF Computer Graphics Lab