Despite ethical claims that civic societies should foster intergenerational integration, age-segregation is a widespread yet understudied phenomenon. The purpose of this study was to understand the reasons that led community-dwelling older Americans to relocate into senior housing. Qualitative data were collected through participant observation and ethnographic interviews with 47 older adults living alone in San Francisco, California. Half of study participants lived in housing for seniors, the other half in conventional housing. Data were analyzed with standard qualitative methods. Findings illuminate the dynamics that favor age-segregation. Senior housing might be cheaper, safer, and offer more socializing opportunities than conventional housing. Yet, tenants of senior housing may also experience isolation, crime, and distress. Findings suggest that rather than individual preference, cultural, political, and economic factors inform the individual decision to relocate into age-segregated settings. Findings also call for an increased awareness on the ethical implications of societies increasingly segregated by age.