ABSTRACT
This chapter presents methodological aspects of the reflexive models of “complex activity” (CA), which is defined as an activity characterized by at least one of the following attributes: the variable technology or/and subject or/and role of object in the target context of activity during the period of activity, the multiplicity of technologies or/and subjects or/and objects. The variability and multiplicity of the subject and object forces the consideration of the subject and object in addition to the activity itself, which makes the models reflexive. CA is a complex system, so system theory is applicable to study such activity. The most influential elements of an external environment are considered: the subject who implements the activity and the object of activity, which has to be transformed as the result of activity. The subject is exposed to external constraints, translating them into activity; also the subject interprets the stakeholders’ needs, performs goal-setting and governs the activity.
