In this essay, the authors propose a three-part ideal-type typology that distinguishes between “ruling monarchy,” “constitutional monarchy,” and what they call “democratic parliamentary monarchy” (or DPM for short). For us, the defining characteristic of a DPM is that only the freely elected parliament forms and terminates the government. In a constitutional monarchy, by contrast, there is a strong element of dual legitimacy in that parliament and the monarch need each other’s support in order to form or terminate a government. In still greater contrast, in ruling monarchies the monarch can often unilaterally form or terminate the government. Moreover, each of these three types comes with its own set of patterns concerning the rule of law, constitutional constraints on the monarch, the status of parliament, and the relative autonomy of the judiciary.