SOFA is a C++ library primarily targeted at medical simulation research. Based on an advanced software architecture, it allows to (1) create complex and evolving simulations by combining new algorithms with algorithms already included in SOFA; (2) modify most parameters of the simulation – deformable behavior, surface representation, solver, constraints, collision algorithm, etc. – by simply editing an XML file; (3) build complex models from simpler ones using a scene-graph description; (4) efficiently simulate the dynamics of interacting objects using abstract equation solvers; and (5) reuse and easily compare a variety of available methods (see Figure 1 ).
A tutorial on SOFA has been given at the IEEE Virtual Reality Conference, La Fayette, FEbruary 2009. It has been used as software platform for several publications of the team  ,  ,  ,  .
SOFA has been chosen as implementation platforms for the European project Passport for Liver Surgery, the national projects ANR Vulcain, BQR Fissure, our participation in ANR RepDyn,