The article presents an approach to the development of systems based on a methodological approach. Information system may be represented as a methodological system, which describes the structure and content of the work of all actors involved in the development process. The concept of mechanism is proposed to use as methodological form of work representation. Mechanisms in the system have interpenetration and interaction and form a structure which is a form of methodological knowledge of system creation. Methodological approach applications will simplify the development and adaptation of information systems.