Models and software are provided for the analysis and simulation of upper limb musculoskeletal systems. The DSEM contains source code, data files and Windows binaries for the inverse-dynamic analysis of muscle and joint loading on the upper limb. We make these packages available to the community for the convenience and benefit of fellow researchers, subject to the terms of the user agreement. However, we do not have the resources to offer support for the use of the models. See the project wiki for frequently asked questions, and a brief user's guide. We will endeavour to answer reasonable questions on the use or understanding of the software where time permits, but cannot guarantee any particular level of response.