We use administrative data to examine the various milestones achieved and pathways followed by new Social Security Disability Insurance (DI) and Supplemental Security Income (SSI) awardees. Our findings show that 80% of DI-first awardees and 53% of SSI-first awardees either achieved none of the milestones we tracked in the 10 years after their initial award or their only milestone was death or attainment of full retirement age. Furthermore, many DI and SSI awardees who achieved work- or program-related milestones during the analysis period did not make additional progress toward exiting the program. For example, one third of DI-first and one fifth of SSI-first awardees who enrolled in employment services had no other milestones and one quarter of DI-first awardees who completed a trial work period either had no other milestones or their only additional milestone was enrolling in employment services. We also found that approximately one quarter of SSI-beneficiaries who later received DI had their SSI benefits suspended and terminated due to excess income that included DI payments as the only additional milestones. Finally, our analysis reveals great diversity in the paths taken to achieve work- and program-related milestones, which policy makers should consider when designing interventions to help awardees return to work.