After discussing survey data from three western United States cities that indicates that social integration (SI) and collective efficacy (CE) have significant, direct impacts on fear of crime, with SI also affecting CE, the author contends that by studying theory constructs and validation processes researchers may enhance their theoretical understanding of SI, CE, and fear of crime. Following a discussion of Gibson et al.’s SI and CE measurement models, the author argues that Gibson et al.’s stacked model test fails to meet the criteria for a low level of similarity when using it to test fear of crime rates across the cities surveyed. Turning to a discussion of the ways to distinguish SI from CE, the author focuses on contextual perspective and content of items, indicating that in order to develop appropriate indices for constructs for modeling fear of crime, future studies need to employ a full set of indices so that researchers can analyze patterns of convergent versus discriminant validity. The author concludes that in order to establish the truth of the dynamics noted by Gibson et al., researchers need to develop a panel design, and a clustered sample design, a multi-trait multi-method; and devote conceptual attention to clarifying the differences among social capital, social networks, organizational participation, collective efficacy, willingness to intervene, informal social control, sense of community, attachment to place, and social homogeneity as they apply to fear of crime. References