The Bulletin of the World Health Organization is an international journal of public health with a special focus on developing countries. Since it was first published in 1948, the Bulletin has become one of the world's leading public health journals. As the flagship periodical of the World Health Organization (WHO), the Bulletin draws on WHO experts as editorial advisers, reviewers and authors as well as on external collaborators. In this month's issue: Knowledge is power; information is liberation; Public health management of mass gatherings: the Saudi Arabian experience with MERS-CoV; Frequent exposure to suboptimal temperatures in vaccine cold-chain system in India: results of temperature monitoring in 10 states; Trends in caesarean delivery by country and wealth quintile: cross-sectional surveys in southern Asia and sub-Saharan Africa; Monitoring service delivery for universal health coverage: the Service Availability and Readiness Assessment; Management of children exposed to Mycobacterium tuberculosis: a public health evaluation in West Java, Indonesia; The impact of rural health system reform on hospitalization rates in the Islamic Republic of Iran: an interrupted time series; The ethics of feedback of HIV test results in population-based surveys of HIV infection; Rapid monitoring in vaccination campaigns during emergencies: the post-earthquake campaign in Haiti; Local production of WHO-recommended alcohol-based handrubs: feasibility, advantages, barriers and costs