Pathfinders unpacks the performance improvement models that can be best used to aid organizations in going beyond training and achieving the needed performance results. Part I introduces the context of the attention converging on performance improvement, and why. Part II presents the preeminent performance improvement models that have stood as solid foundations on which to research theory or practice applications. It also offers a metamodel that provides a common framework for these models and shows how they relate to interventions that can be used to improve performance. Part III presents an unprecedented collection of biographies and bibliographies that provide an overview of the dominant performance improvement models.