Informal caregivers play an increasingly important role in caring for aging Americans. Yet existing social policies that could support informal caregiving have experienced "policy drift," a failure to adapt to social risks that develop after policies are initially enacted. This article examines policy makers' success at updating seven major policies to address caregiver needs. It draws on an original data set of legislation in this area introduced between 1991 and 2006 (n = 96). Findings indicate that drift is more likely when policy updates are costly, lack support from members of majority parties in the House and Senate, and fail to generate bipartisan support.