The present invention provides .beta.-hydroxy-.gamma.-aminophosphonates, .beta.-amino-.gamma.-aminophosphonates, and analogs thereof that inhibit carnitine acyltransferases. The invention also provides compositions comprising these .beta.-hydroxy-.gamma.-aminophosphonates, .beta.-amino-.gamma.-aminophosphonates, and analogs, and methods of the use of such compounds and compositions in the treatment, amelioration or prevention of pathological conditions, diseases or disorders that are linked with fatty acid metabolism, such as non-insulin dependent diabetes or obesity. The invention also provides processes for the preparation of such compounds and compositions.