This Account summarizes predominately our own experiences in developing microwave-heated palladium-catalyzed Mo(CO)(6)-mediated gas-free carbonylative reactions, although contributions from other groups, including non-palladium-catalyzed examples, have also been covered. Presented reactions include amino-, amido-, and alkoxycarbonylations as well as carbonylative cyclizations and carbonylative cross-couplings, using Mo(CO)(6) as a solid source of CO. The methodology was developed mainly for rapid small-scale applications, avoiding the problematic use of gaseous CO in a standard laboratory. In most cases, the reported Mo(CO)(6)-mediated carbonylations were conducted in sealed vessels and with reaction times of less than 1 hour. The Account also highlights relevant applications in medicinal and high-speed chemistry.