5-HT2 receptors are G-protein coupled receptors that currently comprise threesubtypes: 5-HT2A, 5-HT2B and 5-HT2C receptors. The subtypes are related in theirmolecular structure, amino acid sequence and signaling properties. 5-HT2A and 5-HT2Creceptors have a widespread distribution and function in the central nervous system.5-HT2A and 5-HT2C receptor antagonism is a property of certain antipsychotic and antidepressantdrugs. 5-HT2B receptors have a restricted expression in the central nervous system. They have animportant role in embryogenesis and in the periphery. In this article, selected aspects of 5-HT2 receptor researchare reviewed for each subtype under three main headings : (i) genes, protein structure and receptor signaling;(ii) receptor localization with emphasisontheCNSand(iii)compounds. Thegeneraldiscussion reflects on the reasons for the limited success in the clinic of 5-HT2 receptor subtypeselective drugs.