OBJECTIVES: To develop a checklist of essential items, which authors should consider when reporting studies of mapping to preference-based measures from other outcome measures. The aim of the checklist (the MApping onto Preference-based measures reporting Standards (MAPS) statement) is to promote complete and transparent reporting by researchers.  METHODS: A working group of health economists and a Delphi methodologist was convened. Candidate items for the checklist were identified through a structured review of the literature and reviewed by the working group. A modified Delphi survey, with representatives from academia, consultancy, health technology assessment agencies and the biomedical journal editorial community, was used to identify a list of essential reporting items from the set of candidate items. The survey was administered via the web in two rounds.  RESULTS: