"Psychedelic art" can be defined as artwork manifested in the context of the ingestion of LSD-type drugs and related substances. There is a long history of such work dating back to ancient times (picturing mushrooms and other plants with psychedelic effects) as well as more recent anecdotal first-person accounts and various collections of psychological data resulting from experiments and interviews. One such collection includes the studies by Krippner of over 200 artists, writers, and musicians who referred to their artistic productions as "psychedelic" because they had some connection with their occasional or frequent use of these substances. Although there were no commonalities characterizing all of their paintings, films, poems, novels, songs, or other works, several frequent themes were noted following content analysis of the interview reports. The results of this group of studies, as well as those of more structured explorations, attests to the importance of this topic for humanistic psychology with its emphasis upon creativity, human potential, and exploring the wide range of human experience.