This report provides a comprehensive picture of individuals’ patterns of participation in the Food Stamp Program (FSP) during 2001-2003, a period of steady caseload growth. Based on data from the Survey of Income and Program Participation (SIPP), the research explores reasons that individuals enter and leave the FSP, how long they stay on the program, whether they return to the program after exiting, and what factors distinguish those who make greater use of the FSP than others. The research also examines whether participation patterns in 2001-2003 changed from patterns in the 1990s.