This project provides an OpenSim analysis to minimize both joint reaction loads and muscle activations in a moving musculoskeletal model. The analysis, called JointLoadOptimization, is provided as an independent plugin that users can link with OpenSim. JointLoadOptimization is highly configurable version of static optimization, providing an xml interface for customizing the cost function. The cost function can include independently weighted components of the joint reaction force and moment for any joint in the model, as well as weighted muscle activations.