Encyclopedias, Almanacs, Transcripts, and Maps
- Institut für Grenzgebiete der Psychologie und Psychohygiene (Institute for Border Areas of Psychology and Mental Hygiene)
- Institut Général Psychologique
- Institut Métapsychique International
- Institute for Anomalistic Criminology (IAC)
- Institute for Parapsychology
- Institute for Spiritualist Mediums
- Institute for the Development of the Harmonious Human Being
- Institute for the Study of American Religion (ISAR)
- Institute for Yoga and Consciousness
- Institute Magazine
- Institute of Divine Metaphysical Research
- Institute of Electrical and Electronics Engineers
- Institute of Noetic Sciences (IONS)
- Institute of Professional Engineers New Zealand
- Institute of Psychophysical Research
- Institutio "Gnosis" per la Ricérca Sulla Ipótesi della Sopravvivenza
- Institutional Biosafety Committees
- Institutional Review Boards
- Institutionalization and Deinstitutionalization
- Instituto Argentino de Parapsychología