In the UK the rules governing caretaker situations have historically been underspecified. The UK's constitutional traditions, such as prime ministerial discretion to time elections and its two-party system, have in the past limited the frequency and duration of caretaker periods. However, the recently lengthened election timetable, new constraints on the executive introduced by the Fixed-term Parliaments Act (2011), and a decline in the dominance of the two largest parties are raising the risk that the UK will experience caretaker periods more often and for longer stretches of time. In this paper, we offer an analysis of the UK's current caretaker provisions and conclude that the existing conventions are insufficiently detailed and can render such periods problematic and controversy-prone. Important lessons, we suggest, can be learned from reforms in other Westminster systems, and from the caretaker rules of other countries. [ABSTRACT FROM AUTHOR]