Sociologists, health specialists, and other specialists mainly from North America present 13 chapters on underserved and socially disadvantaged groups, particularly people of color, rural Americans, and aging populations, in the context of health and healthcare disparities and inequalities. They address mental health related issues in relation to race and ethnicity, including mental health pathways for girls of color, familial support and mental health services use by Asian American and Latinx older adults, and psychological distress differentials as a function of the subjective social status among Latino subgroups in the US; other types of health problems, including environmental inequality and health, autism spectrum disorders and aging adults, hepatitis C and support groups in rural communities, and overall perspectives on health, well-being, and nutrition by children; gender concerns in underserved and socially disadvantaged groups, in terms of leprosy in southeast Nigeria and gender inequalities in health policy for the care and management of thalessemia; and issues linked to healthcare workers, including gender politics, socially disadvantaged groups who are healthcare workers, and migrant women who work as home care assistants.