This essay presents the rationale to consider anomalous experiences (AEs, such as synesthesia, lucid dreaming, hallucinations, psi-related experiences, and near-death experiences) as an essential topic in psychology. These experiences depart from the typical or customary characteristics of consciousness (e.g., out-of-body experiences), or from ordinary or normative consciousness (e.g., synesthesia), and sometimes offer an alternative perspective to the nature of self and reality. We review the concept of AEs, methodological issues, and research findings, including their relation to individual differences, psychopathology, culture, and positive psychology. We suggest that mainstream psychology has neglected the study of AEs far too long, although they often engender profound and sometimes highly positive personal and social consequences, and provide valuable insights into the full range of human experience. We propose that the time is ripe to advance the scientific interest in AEs and subject them to rigorous empirical examination in studies that explore their prevalence, phenomenology, and sequelae, and take into account the direct and interactive effects of multiple variables (e.g., genetic predisposition, psychophysiology, personality differences, sociocultural factors). This will extend the purview of inquiry and understanding of our uniquely human nature and potential.