Malingering and related attributions, including invalid response set, are critical issues in forensic disability and related assessments (FDRA). In particular, the first chapter on the topic in the handbook focused on definitions, psychological tests to use, failure criteria, and base rates. This second chapter considers factors that influence base rate estimates, test scores, and failure criteria. The first chapter on malingering in the handbook had found a range to represent the base rate of invalid response set and related attributions in FDRA, and here the chapter authors list provisos that are applicable to it. There are numerous factors that influence tests, including their properties and how they are used. The chapter authors review how malingering in the criminal context differs from malingering in the civil context. As for research recommendations, the field of psychological injury and law needs programmatic research initiatives on key issues. The goal of this chapter and the prior one is to offer usable directions for practice, research, and court.