Criminal responsibility refers to the degree to which an individual is accountable for an illegal act that he or she committed given idiographic factors such as age, cognitive abilities, and psychological functioning (Packer, 2009). Thus, perception of criminal responsibility has the potential to greatly impact forensically involved individuals, and most often forensically involved individuals living with severe and persistent mental illness and/or cognitive limitations. This paper focuses on international and cross-cultural perspectives on criminal responsibility; the topic is of importance because mental health professionals may perform evaluations of criminal responsibility, and potentially testify in this regard, in jurisdictions with dissimilar perspectives and/or policies related to criminal responsibility. Specifically, this article discusses the similarities and differences between several geographic areas' definitions of criminal responsibility, evolving legal standards, and the apparent relevance of formal diagnoses in determining criminal responsibility. Variation in perceptions of treatment to rehabilitate mentally ill offenders and the potential legal consequences of a finding of guilt or nonguilt by reason of insanity are also discussed. Findings emphasize that mental health experts who perform criminal responsibility evaluations must be attuned to the specific context in which a defendant is being tried, particularly if practicing in multiple jurisdictions, and that consumers of criminal responsibility research should attend to the broader social context(s) in which each research study is conducted and findings are interpreted.