This article surveys the literature on the reactivity of thiophenes and benzothiophenes published since the appearance of the third edition of Comprehensive Heterocyclic Chemistry. Two areas that have received maximum attention are: (1) homo- and cross-coupling reactions leading to C C bond formation with high site selectivity and under mild reaction conditions, as well as the regioselective introduction of heteroatom substituents and (2) dithienylethenes and their symmetry-allowed photocyclized isomers, with special reference to the use of this photochromic system as photoswitching units.