Runaway behaviors among teenagers have been studied for some 40 years. Still, because runaway and homeless youths have often been confounded, little is known about what really defines a runaway adolescent. This study targets three objectives in a mixed-method design relying on data from official files and interviews: the descriptions of teenagers reported as missing (e.g., age, sex, runaway duration and reiteration, place left behind, type of caller reporting the child as missing, motivation for closing the file) and the understanding of runaway pathways and dynamics. These studies can contribute to prevention and intervention programs by providing new perspectives on how runaway experiences should be understood in light of the adolescent process.