Due to the challenge of adapting to an increasingly complex environment, organizations have to be simultaneously efficient and innovative. This ambidextrous proceeding leads to many tensions and paradoxes at the operational level. Therefore, operational leaders have to think and act paradoxically in order to induce sustainable ambidexterity. The question of how operational leaders of stable corporations perceive and manage tensions in order to achieve an ambidextrous organization has not previously been investigated. As a consequence this master thesis uses the ambidextrous approach as well as the paradox perspective as a theoretical framework. The qualitative single case study presented herein shows that executives have to develop and improve underlying competencies for managing tensions in order to enable ambidexterity. In addition to cognitive, behavioral and emotional competencies, conceptual competence plays an essential role. Because there is a strong correlation between the competencies, the paradoxical mindset and associated management practices, the latter will evolve automatically over time. Moreover a graphical illustration shows the relationship of the results in order to clarify how operational leaders in stable corporations should deal with tensions.