Here's how I got the Generic Function code running starting with a clean image. (Please use an expendible image if you experiment with the code.) File in: ADVANCED install.st (take everything) EVENTS events.st The entire Refactoring Browser John's MethodWrapper.st, Synchronization, Interaction, and Coverage files. From this directory: Method-Wrappers.st (slight changes from Brant, may not be needed) Generic-Functions.st generic.st MultiMethod-Menagerie.st That Be aware that this is very new, experimental code, and you should have no difficulty breaking it. To run a GF: Go to MultiMethod-Menagerie>>ethology|Mouse>>moveThrough: "Do" the line that makes the GF's MethodCombination be SubStandardMethodCombination "Do" the line that sends a Land to a Mouse.