The investigation of natural and synthetic cannabinoid ligands, including (-)-Delta(9)-tetrahydrocannabinol, cannabinol, cannabidiol, HU-210, HU-211, CT3, CP 55, 940, WIN 55, 212-2, SR 14, 1716A, anandamide, 2-arachidonoylglycerol, and numerous novel analogs, has led to important findings that have contributed to a better understanding of the role of these compounds in physiological processes. Their potential use for medicinal purposes is also better understood as a result.