The response of law enforcement agencies to runaway and homeless youth varies by community and individual officer. Some police departments perceive runaways as criminals while others recognize runaways as victims of family conflict or uncaring institutions who need to be helped. But in many cases police do not "see" runaways at all. This guidebook was created to encourage and facilitate collaborative efforts between law enforcement agencies and agencies that serve runaway and homeless youth. The goal of this document is to help law enforcement agencies and programs serving runaway and homeless youth to: assess the need for collaboration in their community; develop a process by which they can create a collaborative arrangement that responds to their needs; increase referrals by police and strengthen services for runaway youth and their families; reduce unnecessary adjudication and incarceration of runaway and homeless youth; and monitor and refine their collaboration. The chapters are as follows: (1) Youth at Risk; (2) Services for Runaway Youth; (3) An Introduction to Interagency Collaboration; (4) Case Studies; (5) Designing and Implementing an Interagency Collaboration; and (6) Conclusion. Four appendixes include a bibliography, resource organizations, sample interagency agreements, and evaluation resources. (JBJ)