Throughout history, social work has played a significant role in the changing healthcare delivery system. This chapter highlights the history of healthcare and social work, including the roles social workers are engaged with diverse populations. It underscores the unique contributions and challenges that social workers are involved with in practice, policy, and research. Social workers have advocated for human rights and social justice throughout history. Social workers can help to change the healthcare delivery system that embraces collaboration with the individuals, families, communities, and other disciplines to insure good health for all members of society. Social workers recognize the dignity and worth of all people as well as the influence of the environment on human life. The recognition of healthcare disparities that continue to exist in society is a major concern of social workers responding to the needs of vulnerable populations.