The past ten years have seen an avalanche of literature on the rule of law, but little agreement on a definition of the concept – if it is defined at all. The present article offers a conceptual framework to deal with this situation. Departing from the two main functions the rule of law intends to serve – protecting citizens against the state and against one another – it dissects the various definitions in use into elements. These elements are discussed one by one and arranged in three categories: procedural elements, substantive elements and control mechanisms. The result may not only be helpful in structuring debates about the rule of law, but also in evaluating claims about the success or failure of ‘rule of law development’. Finally, the article contains suggestions on how to use this framework as a starting point for interdisciplinary research into the rule of law.