A physiological role for the 5-HT7 receptor within the central nervous system has been clearly established in circadian rhythm regulation and in thermoregulation. The early finding that several antipsychotics and antidepressants have high affinity for the 5-HT7R, as well as its demonstrated presence in relevant regions of the brain, has prompted several preclinical studies evaluating the possible involvement of the 5-HT7 receptor in psychiatric disorders and other pathological processes of the nervous system. Interesting findings have also been made in studies focusing on learning and memory. Moreover, a role fo the 5-HT7R has also been suggested in neuroendocrine regulation. Possible functions in the periphery are mostly related to the presence of 5-HT7 receptors on smooth muscle cells. Thus, a role for the 5-HT7 receptor has been suggested in irritable bowel syndrome, the control of micturition, and in the reproductive system.