The author examines the tension that exists between the various components of the separation of powers (in particular the ideas of independence and separation, and the system of checks and balances). He analyses different ways of solving them. Attention is paid, for example, to attempting to supplement the separation of powers with some other normative thesis. The author rejects previous approaches and argues that the components of the separation of powers can be understood as separate principles. Conflicts between these principles should be resolved through proportionality.