This document updates the 2009 ECDC guidance on chlamydia control in Europe. It was developed by a technical expert group which conducted a critical review of the scientific evidence on the epidemiology of chlamydia and the effectiveness of screening programmes. The aim of this guidance is to support Member States to develop, implement or improve strategies for chlamydia control. This guidance describes the current evidence base behind the proposed options, highlights key gaps in knowledge, and suggests effective options for national chlamydia control strategies. It is directed primarily at policy advisors but should also be useful for programme managers and experts in sexual health.