This document establishes the first Code of Ethics and Safety Guidelines for the emerging field of darkness therapy, prepared by the Darkness Therapy Institute with contributions from its Advisory Board. It addresses the unique ethical considerations of prolonged darkness immersion, including screening and readiness, informed consent, navigating non-ordinary (altered) states of consciousness, power dynamics, trauma-informed care, and professional boundaries. The Code complements existing profession-specific ethical standards with parameters specific to environmentally-induced sensory reduction and the heightened vulnerability that accompanies immersion in complete or near-complete darkness. Two supplementary documents are included as appendices: a summary of the Core Practice Principles and a Facilitator Quick Reference Guide.