The Manual for Parasitological Surveillance in Prevention of Reintroduction or Re-establishment of Malaria in Sri Lanka (2019) provides guidelines to health professionals on how to conduct effective malaria surveillance to prevent the reintroduction of the disease in Sri Lanka, which was certified malaria-free in 2016. The manual outlines strategies for active and passive case detection, laboratory diagnosis, case investigation, foci investigation, and follow-up measures. It emphasizes targeted screening of high-risk populations, including travelers and migrant workers, and explains the importance of prompt reporting, accurate parasitological confirmation, and coordination between healthcare levels. The overall goal is to maintain Sri Lanka’s malaria-free status by ensuring early detection and rapid response to any imported or locally suspected malaria cases.