This report, the first in a series relating to disconnected young adults commissioned by JobsFirst NYC, examines what is known about New York City's disconnected youth--16 to 24 year-olds who are not working and not in school. The report explores the roots of disconnection and identifies five priority populations of young people who are at high risk of becoming disconnected. It presents information about specific areas of the city with high concentrations of disconnected young people and summarizes a number of promising strategies for reclaiming this important human resource. The aim is to provide this information in a succinct and accessible format to encourage program developers, funders and government officials in New York City to support the creation of more effective and better coordinated solutions for successfully reengaging disconnected youth. (Contains 5 figures, 1 table, and 77 endnotes.) [Through the support of the Achelis Foundation, JobsFirst NYC funded this report.]