In the article, which is literature review highlighted the phenomenon of increasing of complexity in organization. It was presented the prerequisites and implications of the rising complexity. There was indicated also of need for action to reduce the complexity (of both the strategic and operational dimensions of the organization). The most important conclusions are following: - the essence of complexity comes down to a multitude of elements that influence each other, increasing their interdependence and their diversity, - performance of an organization the conditions necessarily leads to an increase in the complexity, - striving for simplicity, not allowing the uncontrolled rise of complexity becomes a major imperative for the management of contemporary organization.