We demonstrate how the computer-based technique of multi-body dynamics analysis (MDA) can be used to create schematic, but informative three-dimensional (3D) representations of complex muscle anatomy. As an example we provide an overview of the head and neck muscles present in Sphenodon (Diapsida: Lepidosauria: Rhynchocephalia). First a computer model based on micro-computed tomography datasets provides a detailed and anatomically correct three-dimensional (3D) framework to work from. Secondly, muscles are represented by groups of cylinders that can be colour coded as desired. This allows muscle positions, attachment areas, and 3D orientation to be visualised clearly. This method has advantages over imaging techniques such as two-dimensional drawings and permits the form and function of the muscles to be understood in a way that is not always possible with more classical visualisation techniques. ; Neil Curtis, Marc E. H. Jones, Susan E. Evans, Paul O’Higgins, and Michael J. Fagan