Self-transcendence involves reduced self-saliency (ego disillusionment) and increased connection, and interest in the topic has grown over the past decade. Several measures with some psychometric validity and reliability exist, but no prior review has systematically described, contrasted, and evaluated the various methodological approaches—including questionnaires, neurological and physiological measures, and qualitative methods. This review fills that gap by describing existing measurement methods, assessing their strengths and weaknesses, and suggesting future research directions and recommendations for selecting appropriate methods based on research context.