These guidelines, based on lessons from past and current TIP data collection efforts, are for frontline staff from governments, international organizations (IOs) and non-governmental organizations (NGOs) who are engaged in TIP data collection. The guidelines are based on good practice and lessons from The Science (and Art) of Understanding Trafficking in Persons: Good Practice in TIP Data Collection and offer step-by-step guidance and checklists on how to conduct TIP data collection in a constructive and ethical way and in line with existing work and mandates.