Enormous gaps between HIV burden and health care availability in low-income countries raise severe ethical problems. This article analyzes four HIV-priority dilemmas with interest across contexts and health systems. We explore principled distributive conflicts and use the Atkinson index to make explicit trade-offs between health maximization and equality in health. We find that societies need a relatively low aversion to inequality to favor treatment for children, even with large weights assigned to extending the lives of adults: higher inequality aversion is (...) needed to share resources equally between high-cost and low-cost treatment; higher inequality aversion is needed to favor treatment rather than prevention, and the highest inequality aversion is needed to favor sharing treatment between urban and rural regions rather than urban provision of treatment. This type of ethical sensitivity analysis may clarify the ethics of health policy choice. (shrink)