According to his own account, while experimenting with sleep-learning in 1958 Monroe experienced an unusual phenomenon, which he described as sensations of paralysis and vibration accompanied by a bright light that appeared to be shining on him from a shallow angle. Monroe goes on to say that this occurred another nine times over the next six weeks, culminating in his first out-of-body experience. Monroe recorded his account in his 1971 book Journeys Out Of The Body and went on to become a prominent researcher in the field of human consciousness.

Monroe later authored two more books, Far Journeys (1985) and Ultimate Journey (1994).

In 1978 he founded The Monroe Institute, a non-profit education and research foundation describing itself as being "devoted to the exploration of human consciousness".

In his last book Ultimate Journey there is a chapter "About the Author". In this chapter it is said that Robert Monroe is directing Monroe Institute - from There, meaning that he is able to take part in his Institute life from his post-death state.

In 1975, Monroe registered the first of several patents concerning audio techniques designed to stimulate brain functions until the left and right hemispheres became synchronized. Monroe held that this state, dubbed Hemi-Sync (hemispherical synchronization), could be used to promote mental well being or to trigger an altered state of consciousness. Monroe's concept was based on an earlier hypothesis known as binaural beats and has since been expanded on a commercial basis by the self help industry.

During the "Project Stargate" studies period into what is now called Remote Viewing, Robert Monroe's interests and research in Out of Body Experience (OBE) extended into the accepted scientific scope of Remote Viewing. His personal friendship and association with U. S. Army officers, Frederick "Skipp" Atwater, and Joseph McMoneagle from Ft. Meade. Both expanded remote viewing into the remote past and future. McMoneagle would later date and marry Monroe's stepdaughter, Nancy Honeycutt, and become associated with research and study at The Monroe Institute.U.S. Media consultant and White House speech writer, Donald A. Stewart, who was also a personal friend and a former student in media, were influenced and inspired by Monroe, with their mutual interests into parapsychology and psychical research.

Robert Monroe was the author of three books:

• Journeys Out of the Body (1971) ISBN 0-385-00861-9
• Far Journeys (1985) ISBN 0-385-23182-2
• Ultimate Journey (1994) ISBN 0-385-47208-0