The paper surveys the current debate on central bank independence and points to some of the open questions. There is a broad consensus on the economic and political advantages of an autonomous central bank but less is known about the background of such an institution. Even though the question is of some importance, the theoretical literature has little to say about the forces of institutions that enable a government to effectively commit itself to central bank independence. The empirical literature is much better euqipped to reveal the effects of central bank autonomy then to uncover its determinants. Two of the reasons are that the present discussion more or less restricts itself to law-based cross-country studies and that it ignores the time dimension. In both respects qualitative and economic-history methods could help to solve some of the remaining theoretical and empricial problems.