Interface Issues in Visual Shell Programming Francesmary Modugno A visual shell, such as the Apple Macintosh Finder, is a direct manipulation interface to a file system. Although such systems are easy to use, they are are difficult to program, especially for non-programmers. This paper introduces Pursuit, a visual shell design that combines visual program specification, visual language representation and object-oriented techniques, to address some of the problems of visual shells, and discusses some of the issues relevant to making Pursuit's approach viable. First, Pursuit extends the concept of a concrete, directly manipulable object to all interface objects, so that the output of any utility can be selected as input ({\it i.e.}, piped) to other utilities. Second, Pursuit incorporates a Programming by Demonstration (PBD) system into the interface. This enables non-programmers to construct programs by manipulating representations of file system objects, such as files and folders, directly in the interface. Finally, Pursuit introduces an object specific, state-based visual representation language for programs. Programs are static, editable representations of objects and behaviors that reflect the interface. Hence, Pursuit provides a uniform model -- that of object and behavior -- for users to learn in order to understand, navigate and program in Pursuit.