The KBVision System Visual Programming Environment is the execution interface by which users investigate potential solutions to their IU problems. This interface shows execution blocks, called "Tasks", and the flow of data and control via connections, called "arcs". During execution, colors change on arcs and Tasks, indicating the state of execution and existence of variables. The user constructs visual programs in this environment by specifying or selecting Tasks and by drawing arcs. The result is a dataflow representing some experiment or program. These programs, called "graphs", act just like any other Task, and can be included in other graphs, building hierarchies of experiments in a modular and reusable manner. Experiments can be shared with a team of workers, or the entire user community if desired. Within KBVPE the user can specify constructs that branch, depending on variables or results of previous processing. The user may specify iteration and recursion so that the same algorithm can be run with a set of variables and/or a set of images.