Information on compost organic matter stability is necessary to anticipate the effects of compost application on soil properties. Such information will soon be required by French legislation. The main objectives of the present work were: (1) to study the influence of the composting process and the composted waste on the kinetics of stabilization of organic matter during the composting process; (2) to validate physicochemical indicators of compost stabilization and also rapid tests used by the compost producers on the composting plants in order to be able to follow compost stabilization during the process. Ten compost windrows were sampled after 3, 4 and 6 months of composting at plants where green wastes (GW), biowastes (BIO), sludge (SG) or municipal solid wastes (MSW) were composted. In some plants, the composting process was accelerated by enforced aeration. The stability of the organic matter was assessed by laboratory incubations during which organic matter mineralization was followed. Maturity tests...