Clinical forensic psychology can be defined as assessment, treatment, or consultation that revolves around clinical issues occurring in legal contexts. This chapter discusses methodological challenges and approaches that arise in three primary areas of clinical forensic psychology—descriptive forensic assessment (e.g., psycholegal capacities), predictive assessment (e.g., violence risk assessment), and evaluation of legally relevant constructs (e.g., psychopathic personality and malingering). Forensic assessment research is challenged by varying legal definitions, lack of gold standards for validation, insensitive predictor and outcome measures, dichotomous legal outcomes versus continuous psychological outcomes, low and varying outcome base rates, ethical constraints placed upon researchers by legal realities, and studying constructs defined partially by deceitfulness. Research of descriptive questions include literature surveys, polling experts, theory‐based development, and evaluating agreement between test classification and clinicians' assessments. Although postdictive and pseudoprospective designs are common in predictive research, they have shortcomings best overcome through use of prospective designs that include multiple measures and sources of data. Repeated‐measures prospective designs, case‐crossover designs, and naturally occurring field experiments offer novel opportunities to study predictive questions. Research on psycholegal constructs commonly relies on factor analytic and prototypical approaches to explicating psycholegal constructs. Simulation and analogue studies are often used to study constructs such as malingering.