We have developed a general purpose multidimensional image processing, analysis, and visualization software system for biomedical applications. This system, called Viewit, is an interpreter for an image processing language based upon a stack calculator paradigm where each stack element is a multidimensional array. Over two hundred primary functions are available for general purpose multidimensional image processing applications including Fourier transforms, back-projection, n-dimensional neighborhood operations, volume rendering, and animation. Viewit is available for most Unix based computers and includes specialized code for Cray vector architectures and the Connection Machine. Distributed image display interfaces are available using several different protocols, including X Windows. Viewit can be downloaded through Internet network access to NCSA. Viewit has evolved over a three year period through collaboration with researchers in the fields of 3-D nuclear magnetic resonance (NMR) microscopy, confocal microscopy, and other biomedical imaging areas. It can be used as a flexible research tool both for the development of analysis methods and for production application processing. In this article we discuss some of the features of the system and report on application research results.