The social service workforce plays an invaluable role in supporting, protecting, and advocating for vulnerable children and families. This technical report describes the composition of the social service workforce drawn from several sources of data, including a literature review primarily focused on workforce issues in HIV/AIDS-impacted countries in sub-Saharan Africa. It is intended to help the field move toward a common understanding of functions associated with different cadres within the social service workforce, titles associated with workers who perform these functions, and education or training that is typically associated with these cadres. Taking into consideration the differences across countries, the authors propose additional emphasis on some broad areas—including examples of promising practices—that will help to clarify the composition of social service workforce. A more in-depth look at how public-sector social service workers are classified in Kenya is available as an annex.