Management of organisations in a global economy, globalisation and governance, and progressively wider and deeper integration processes put forth to managers different levels of hierarchical, multi-dimensional requirements in the sphere of competence, mainly in the fields of knowledge, competences and experience – including managerial competences, personality traits, ethical and moral behaviour (the system goals and values). In the twenty-first century economy based on knowledge and innovation, the manager is the one who has a huge impact on the development of the organisation, a person with a unique opportunity to create his own ideas. This paper discusses various competences of managerial level staff which are a prerequisite for successful organisation management. Among others the following competences are elaborated on: leadership, negotiating, interpersonal, team-working, technical, knowledge management and managerial competences. It is stressed that every manager, regardless of the level of management, position and functions, needs to be effective and efficient in managerial activities. Therefore knowledge and managerial competences, personality, experience, intelligence, imagination, are the key traits that should characterise a manager.