GIMIAS (Graphical Interface for Medical Image Analysis and Simulation) is a software framework designed to be an integrative tool for fast prototyping of medical applications. It is a workflow-oriented environment for advanced biomedical image computing and simulations, and it can be extended through the development of problem-specificplug-ins. GIMIAS is particularly tailored to integrate tools from medical imaging, computational modeling, numerical methods and computer graphics to provide scientific developers and researchers with a software framework for building a wide variety of tools. Multi-modal image processing, personalized model creation, numerical simulation and visualization of simulation results are some of the possible applications for which GIMIAS has been designed.