This project investigates the time patterns of receipt and recertification for benefits from the Supplemental Nutrition Assistance Program (SNAP). Using Michigan program administrative data from January 2006 through August 2011, we study benefit receipt and program exit for subgroups including the elderly, disabled, and able bodied adults without dependents. We also examine whether policy changes governing application and recertification rules and procedures affected rates of benefit receipt and program exit, focusing on each subgroup in turn. Important policy changes in this period included the Combined Application Program which simplified enrollment and recertification for SSI recipients, establishment of the Michigan Bridges on-line system, the elimination of mandatory in-person initial application for benefits, and establishment of broad based categorical eligibility for SNAP. Evidence from this investigation will inform policy to improve food security for vulnerable citizens.