Health communications campaigns are a major strategy used by governments to promote health. This article discusses key issues in the ethics of health communications campaigns, including the compatibility of health campaigns with the principle of respect for autonomy and how conflicts with this principle can be justified. Five potential justifications for state-sponsored health communications campaigns are reviewed: the public's health as an independent value; collective efficiency and majoritarian preferences; third party or state's interests; harm to the health of others; and countering the short-term contingencies of a market.