The potential of forskolin as a research tool is just beginning to be realized. Its use has revealed further subtleties to the control of cyclic AMP generation by adenylate cyclase in both solubilized and membrane preparations and in intact cells. It appears that an effect of forskolin will become one of the criteria for implicating adenylate cyclase in any physiological or biochemical response or, conversely, in ruling out an involvement of cyclic AMP. Clinical applications of forskolin as a hypotensive, spasmolytic, lipolytic, or antithrombotic agents or for the treatment of glaucoma or cardiac insufficiency remain other challenges for the future.