A method and a system for verifying properties of a computer program is provided, pertaining to the validity of properties at program points by means of at least one forward analyser and one backward analyser. For each property, in an issuing phase an analyser issues to a centralizer module an assumption on the validity of the property at a point of the program, the centralizer module storing the assumption in a database with an attribute indicating the original analyser and a status indicating that the assumption needs to be verified; in a phase of verifying the assumption, stored in the database, a test analyser is selected to analyse the assumption in cooperation with the other analysers, the centralizer module determining analysers able to cooperate. The verification phase is iterated until all assumptions stored in the base have been analysed by at least one test analyser, a verified assumption being marked as valid.