The SimTK web-based project-hosting platform is designed to accelerate the development and dissemination of biosimulation software, models, and data. Its goal is to encourage and enable researchers to share their resources and knowledge. Started in 2005 with ten individuals from Simbios (the NIH-funded center for physics-based simulations of biological structures, http://simbios.stanford.edu), SimTK has transformed the biosimulation community and is an ideal platform to enable the community to maximize its impact on health and biology. SimTK is forked from FusionForge.