The reactions of acrylonitrile, crotonitrile, propionitrile, and a small set of related reaction products were investigated in high-temperature water. Hydrolysis of the cyano group yielded the corresponding amides, which underwent similar hydrolysis to yield the carboxylic acids. The conversion of acrylonitrile was more rapid than that of its saturated analogue propionitrile, as the unsaturated site of acrylonitrile provided a facile pathway for the formation of alcohols, amines, and ethers. Carbon-carbon bond cleavage pathways involving the hydration of the olefin moiety were also observed for acrylonitrile.