NONMEM is a Fortran program with no user interface. Starting two decades ago, I developed scripts to create graphics and manage files from NONMEM runs. With the collaboration of Steven Shafer, I developed a graphical user interface (GUI), PLT Tools, that performs these tasks and runs NONMEM. The GUI allows the user to control the layout of graphics. In addition, the user can run NONMEM in a variety of modes: covariate search, visual predictive check, likelihood profiling, bootstrap, and jackknife. PLT Tools is available at