[영문]Because social policy making continues to devolve to the state level, social workers should understand how advocacy and policy making occur at that level. Interest groups active in the human services arena were surveyed and data were used to test a model of interest group effectiveness in four states. The independent variables were amount of resources invested, strategy used, relationships with key actors, use of coalitions, and policy positions taken. Results indicate that the model explains low to middling amounts of the variation in group effectiveness. Results also show that the model fits different states to different degrees, indicating that social workers need to approach advocacy in different ways to achieve maximum effectiveness in altering state policy. Implications for altering state policy are provided