Each state plays international roles, that are determined by the internal and international factors. Amongst them two are crucial: the state’s international position and its international identity. The international role of a state is a dynamic expression of its position, provided the state uses that position actively. A state’s potential is very important and is a function of internal factors: its geographical environment in the wide sense; its population potential; its economic, scientific, and technical potential; and its military potential. Political, historical and cultural factors, however, are also significant. The perception of a state by other actors on the international stage is also a very important factor in that state’s international position and, in consequence, for its international roles. It is closely related to the state’s international identity, i.e., the state’s self-perception on the basis of its sense of distinctness in relation to others and the traits ascribed to it by other states. The ‘international identity’ of a state is made up of its ‘internal identity’, which determines the cohesiveness of its component parts, and its ‘external identity’, which constitutes its distinctiveness in relation to other states. International roles of state are subject to various classifications and typologies. The most comprehensive classification based on the following criteria: the subjective criterion, the objective criterion, the spatial criterion, the time criterion the attitude toward international reality criterion the hierarchic criterion the efficiency of role criterion. The effectiveness of international roles is a phenomenon of considerable complexity. It is an unusually difficult task to appraise the effectiveness of a given actor’s role when it is understood as the cost-efficient realization of a goal. First, costs are hard to measure. Second, in today’s interconnected and co-dependent world, a goal could be realized by many entities. I consider that there are three main factors determining the efficiency of roles: 1) the reasonableness of the role’s conception, 2) the ability and consistency involved in performing the role, that is, the degree of its realization, and 3) the level of support for a role by the other actors in international relations, and particularly among those affected by itthe development of their international roles. The thesis of the article is to say that Poland is a medium size state and is limited in These limitations should be taken into account by decision-makers in the formulation of the tasks and goals of Polish foreign policy.