Sunset clauses set an expiration date on a particular law or set of provisions. The expiration is either automatic or subject to a positive or negative authorisation by the legislature. This publication identifies reviews of emergency law as central to the effectiveness of sunset provisions. After detailing some of the difficulties associated with these reviews, the authors draw on examples from post-legislative scrutiny (PLS) more generally to identify best practices. This is to help identify how those involved in both drafting and reviewing emergency legislation might bridge the gap between the potential of sunset clauses and the realities that often arise.