Psychological injury evaluations represent a rapidly growing referral context for forensic psychologists. Such evaluations require extensive training and competence but are also daunting due to their complex nature and heightened likelihood for adversarial scrutiny. This chapter seeks to educate forensic psychologists of the laws that inform such evaluations. It provides an overview of American tort law and of evidence law as relevant to expert witnesses. It reviews the federal Supreme Court decisions comprising the Daubert trilogy and the Federal Rules of Evidence that incorporate the major aspects of those decisions. Additionally, it provides some helpful guidance in terms of best practices for psychological injury evaluations, preparation for court, and tips for avoiding malpractice lawsuits.