The Lagrangian Coherent Structures (LCS) software elements developed by this project will provide a valuable tool set for fluid mechanics research to extract new discoveries from the vast and growing body of computational and experimental fluid mechanics data. The computation of LCS enables a systematic approach to accurately characterize transport phenomena in complex systems that pose insurmountable challenges to traditional Eulerian approaches. Prior, ah hoc implementations of LCS have already helped in important, real-world challenges including, tracking pollutants in the ocean, developing novel diagnoses and therapies for cardiovascular disease, and helping airplanes to avoid turbulence. We will produce an open LCS software system to provide a modular, extensible and flexible infrastructure to broaden the community of scientists and engineers that benefit from LCS, in problems ranging from fluid dynamics to general dynamical systems. Prof. Shadden will lead the LCS algorithm design and numerical analysis, and Prof. Hart will oversee the package's architectural design and the efficient parallel implementation of its elements.