This policy brief from Chapin Hall explores how young people leave foster care among those who first enter care between ages 13 and 17. The researchers used data from a longitudinal foster care archive of approximately 3 million children nationwide. They analyzed reasons for leaving care by age at first admission and by placement history. They found that age at entry and placement history are both linked to youth outcomes. For example, teenagers who first enter care at age 15 have the highest chance of running away and are less likely to reach permanency than those who entered care earlier in their adolescence, in part because they are more likely to reach the age of majority while in care. Similarly, the types and configuration of placements and the number of placement changes affect the chances of youth reaching permanency or running away while in foster care.