Humanitarian NGOs have made increased use of Private Security Providers (PSPs) over the last decade. There is a gap between the ways that NGOs actually use PSPs and the regulation of this engagement. These guidelines aim to assist humanitarian NGOs in reaching an informed decision about when, how and under what conditions to seek PSP services. The guidelines are aimed at operational managers of NGOs, from headquarter to field level. The guidelines do not only cover armed guarding or armed protection, but can be applied to the wide range of services provided by PSPs. Document also available in French.