Each year more than 25,000 youth age out of the American foster care system to face uncertain futures as young adults. A quarter of them will experience homelessness, and as many as 50 percent will not finish high school. Four years after leaving care, less than half will be employed, and their earnings will remain well below the poverty line. And, they will face higher rates of mental health disorders, early pregnancy and parenthood, and incarceration.

But these young people have an advocate in Wendy Smith, who is determined to improve their lives.

"In the last 20 years, there has been more funding and attention on foster care, but the outcomes haven't improved much," Smith said. "Something more needs to happen."

Smith, who is director of instructional enhancement at the USC School of Social Work and a member of its Board of Councilors, has written a new book, "Youth Leaving Foster Care: A Developmental, Relationship-Based Approach to Practice," which integrates research from multiple disciplines in to practice to provide a new foundation for those who work to improve the lives of youth who have been in the foster care system.

The book provides a comprehensive overview of the challenges foster care youth face and how their developmental paths affect their needs as they leave the system. Smith offers a biological-psychological-social perspective as a theoretical framework to guide programs, policies and services that she says will help these youth transition into successful adult lives. Her relationship-based approach emphasizes understanding attachment experiences and disruptions, as well as the impact of unresolved trauma and loss that she believes will help bridge knowledge and practice.

"The attention has been on the immediate needs of basic survival, but not on the inner person – on the attachments and relationships, or on learning to manage strong and overwhelming feelings," Smith said. "Kids need to develop a sense of self – therefore, they need support."

"Youth Leaving Foster Care" includes a comprehensive look at the history of the system, a discussion about the effects of maltreatment on development, mental health problems and treatment, relevant policy recommendations and existing legislation, transitional living programs, populations that require special treatment, and case examples.

Smith's interest in foster care youth stems from her first field placement as a Master of Social Work student in child welfare. She then went on to write her dissertation on the child welfare scene in Los Angeles County. In 2006, she was asked to design a course for the School of Social Work on transition-age foster youth and wanted to integrate theory with practice but soon realized there was no book that did that. Thus, she began the process of writing "Youth Leaving Foster Care."

"What I hope to accomplish is a more dimensional and complex understanding of the inner and outer person of foster care alumni," Smith said. "There's a need for continuity in their lives, for a network of support emotionally and practically. I'd like to develop programs for foster care alumni that include the opportunity to develop and grow."