This book presents a detailed study of the social support networks and help-seeking experiences of low-income Mexican-origin adolescents from immigrant families in the San Diego and San Francisco areas. Drawing on social network data, interviews, and statistical survey data, the book documents and elaborates on the numerous constraints and social forces that prevent many low-status youth from constructing relationships and social networks that could provide important social support. Sections explore the overlapping realms of the neighborhood, the kinship network, and the school, focusing on the relational dynamics that promote or impede social network development in each context. Constraints on help seeking and network development are mainly divided into two categories: those arising in the social-psychological orientations of adolescents and those identified as institutional structures or organizational features. Special attention is given to those forms of institutional support normally enjoyed by privileged youth but not by working-class youth, such as expert guidance on college opportunities. The findings also suggest how some working-class youth become exceptional cases, weaving social webs that promote persistence in school and empowering forms of resiliency. In both types of cases, the role of social networks in shaping young people's life-chances is elucidated. Appendices define social capital and "institutional support," review research methodology, and present data tables. (Contains 237 references, notes, and an index.) (SV)