Promise theory is a graph theoretical framework for understanding complex relationships in networks, where many constraints have to be met, which we have developed here at Oslo University College, by drawing on ideas from several different lines of research here, including policy based management,graph theory, logic and configuration management. It uses a constructivist approach that builds conventional management structures from graphs of interacting, autonomous agents. Promises can be asserted either from an agent to itself or from one agent to another and each promise implies a constraint on the behaviour of the promising agent. The atomicity of the promises makes them a tool for finding contradictions and inconsistencies.