GENVIEW: and GENCODE: are tools for testing the adaptive nature of a genetic code under different assumptions about patterns of genetic error and the nature of amino acid similarity. GENVIEW: provides a user friendly, point-and-click interface by which a user may reproduce and extend analysis of the adaptive properties of the standard genetic code or any of its secondary derivatives. GENVIEW: is a graphical user interface (GUI) program which runs on Linux, Unix and Microsoft Windows platforms and is based on the GTKf + toolkit. GENVIEW: outputs ASCII configuration files which are interpreted by GENCODE: to perform an analysis. GENCODE: is available for the same platforms as GENVIEW.