This report provides a comparative analysis of three different methods for measuring time spent by adults and children doing agricultural labour: traditional surveys; activity logs, filled in on a daily basis; and GPS trackers worn by participants. The study examines the differences between estimates of time recorded on different activities in cocoa-growing areas of Côte d'Ivoire, discusses reasons for these discrepancies and lessons learnt which are relevant for research protocols in the field. The study was authored by Andrew Dillon, Henriette Hanicotte and Marco Valenza on behalf of IPA. It