The literature on ministerial careers has recently been reinvigorated by individual contributions and collaborative projects. However, few studies of ministerial careers have been able to take into account the varying importance of ministerial positions. Fewer still have taken ministerial careers as their unit of analysis. As a result, they have been unable to account for crucial aspects of these careers. This paper seeks to fill these gaps, linking a crossnational data set on ministerial appointments and terminations with country-specific expert survey data that estimate the importance of ministerial portfolios. Among the new possibilities opened up by this data set of 977 ministerial careers is the systematic description of the structure of ministerial careers incorporating measures of ministerial importance. The paper contributes to the study of ministerial careers by introducing several innovations: a simple analytical framework for the analysis of ministerial careers; a new, crossnational data set on ministerial appointments and terminations incorporting data on ministerial importance; an approach to dealing with the problem of unconfirmed right-censoring that is posed by studying ministerial careers; new approaches to describing and measuring ministerial career structures that the ministerial careers framework and the new data set open up; and an agenda for the future development and use of this new data set on ministerial careers.