I took a few hours this weekend to write yet another sudoku gui. Why? Because the world doesn't have enough implementations. Temporary home is http://libcl.com/tmp/sudoku.lisp A bit rough, but not bad. (load "ltk") (load "sudoku") (sudoku::render) Then open the file menu and select "Generate board". Left click numbers to select them, right click to hide. File->Check board will red flag any squares which are incorrect. Later, Daniel