Traditional efforts to assess behavioral health needs in communities have relied on objective population characteristics to define need. Newer conceptual models must be developed that incorporate survey data into definitions of need. One preliminary model includes resident subjective perceptions of life changes in their personal and social environments. An analysis of survey data from 537 residents of 3 Arizona communities found that life events were significantly realted to psychological well-being, supporting the importance of life change measurement. The meaning and impact of life change may depend largely on its social context. A reanalysis of the tri-city data for a subsample (N=129) of residents 55 years or older revealed that life events which deviated from those of the respondents' age peers affected their well-being independently of more common events. The fit between residents and their social environment may be a significant component of well-being, which highlights the importance of including a social-ecological perspective in assessments of community needs. (Author)