Transpersonal psychology is a sub-field or "school" of psychology that integrates the spiritual and transcendent aspects of the human experience with the framework of modern psychology. It is also possible to define it as a "spiritual psychology". The transpersonal is defined as "experiences in which the sense of identity or self extends beyond (trans) the individual or personal to encompass wider aspects of humankind, life, psyche or cosmos". It has also been defined as "development beyond conventional, personal or individual levels".

Issues considered in transpersonal psychology include spiritual self-development, self beyond the ego, peak experiences, mystical experiences, systemic trance, spiritual crises, spiritual evolution, religious conversion, altered states of consciousness, spiritual practices, and other sublime and/or unusually expanded experiences of living. The discipline attempts to describe and integrate spiritual experience within modern psychological theory and to formulate new theory to encompass such experience.