This guide aims to address the dual challenge of information management in complicated operating environments, and quantifying a hidden crime that is often under-reported and obscured among other human rights violations. It provides guidance on how to integrate counter-trafficking-specific data collection and analysis into existing information management mechanisms which are already well established in humanitarian responses. The goal is to promote an evidence-based decision-making approach that supports the development of new interventions, or the adaption of existing measures, to more systematically integrate counter-trafficking prevention and response into humanitarian contexts.