The practice of image processing inherently requires software development. Creating this technology requires designing, implementing, debugging and testing software applications on a continual basis. Furthermore current software development is typically performed in a distributed environment involving many developers. While the use of open-source software may create collaborative communities that enhance overall technology exchange, it does nothing directly to manage change nor does it address the quality of the underlying software. This paper describes a software development process that has proven vital to the success of the widely used open-source toolkits ITK (itk.org) and VTK (vtk.org). This process facilitates cross-platform development, includes automatic documentation generation, integrates continuous testing, and posts the results of the process on publicly accessible Web pages. The net result is that a responsive feedback loop is created between the developers in the community and automated processes to measure software quality. With this process software converges towards better software as long as the process is enforced. The tools described here are open-source and available for use in academic and commercial applications.