The present review focuses on the Schmidt reaction of chromanones, thiochromanones, 4-quinolones, flavanones, thioflavanones and azaflavanones to yield 1,4-benzoheterazepinones and/ or 1,5-benzoheterazepinone isomers and  their tetrazolo derivatives. Whereas flavanones and 2-arylquinolin-4-ones afford 1,4-benzoheterazepinones and their tetrazolo derivatives, the analogous thiochromanones, thioflavanones and N-methylsulfonylquinolones exhibit similar behaviour of carbon migration to afford mixtures of 1,4- and 1,5-benzoheterazepinones and the tetrazolo derivatives. A survey of the Schmidt rearrangement of flavanoid analogues shows that the mode of nitrogen insertion into the C-ring depends largely on the migratory aptitudes of the aryl (C-3) carbons, which in turn, depend on the electronic effect/nature of the endocyclic heteroatom (X).