Continuing basic research is likely to yield results that could gready enhance the therapeutic potential of cannabinoids. The discovery of cannabinoid receptors makes possible the development of selective cannabinoid agonists and antagonists for use either as therapeutic agents or as experimental tools which may help to establish the physiological roles of cannabinoid receptors and of the endogenous compounds (anandamides) which bind to them. Such developments could lead to the synthesis of drugs with more specific actions than THC or nabilone or cannabis itself - e.g. cannabinoids with anti-emetic, analgesic or anticonvulsant effects without psychotropic or cardiovascular effects. Already there are some pointers in this direction: a selective and potent CB1 antagonist (Rinaldi-Carmona et al., 1994) and two compounds that bind selectively to CB2 receptors (Gareau et al., 1996) have recently been developed. Anandamides have not yet been tested in humans; it is possible that some of these might have specific actions on subtypes of cannabinoid receptors.