To drive health equity into action we need to understand the needs of health disadvantaged populations, identify barriers to equitable access to quality care, and build equity into priority setting, resource allocation and performance management. Health Equity Impact Assessment is a practical and effective planning tool that analyzes the potential impact of service, program or policy changes on health disparities and/or health disadvantaged populations. It can help to plan new services or initiatives or assess and re-align existing programs; and using it has proven valuable to building awareness of and embedding equity within organizations. This is an overview primer that introduces the potential and practice of HEIA. We also have many other resources on our page on equity-focused planning.