Women's health is frequently influenced by social and structural factors, largely beyond women's control, and often entrenched in public policy. Although health is acknowledged to be socially determined, the ways that social conditions affect health are rarely explicated. Grounded theory is a useful method for discovering how structural conditions influence patterns of behavior. We used grounded theory to generate a theoretical understanding of how justice system policy and services related to child custody influence health promotion processes of women and their children after leaving abusive male partners/fathers. In two diverse Canadian provinces, we interviewed single mothers who had left abusive partners as well as frontline workers and policymakers in the justice system. We identified the key dimensions of policy and services that influence the ways in which women and their children promote their health in the context of varying levels of ongoing intrusion as information, eligibility, accessibility, timeliness, human resources, safety, and diversity. In this article, the interplay between theses policy and service dimensions and women's health promotion after leaving abusive partners is discussed and suggestions are made for strengthening "healthy" custody policy.