Background Adolescence is a distinct period of rapid and dramatic biological, cognitive, psychological, and social development. The burden of injuries among young people (aged 10-24) is both substantial and maldistributed across regions and levels of economic development. Objectives Our objective was to compare sociodemographic correlates of injury cause, intentionality, and mortality between Kenya and Oman, 2 countries with different levels of economic development and position in the demographic and epidemiologic transitions. Methods Data on 566 patients in Oman and 5859 in Kenya between 10 and 24 years old were extracted from 2 separate multicenter trauma registries. Multivariable log binomial and Poisson regressions were used to evaluate social and demographic factors associated with injury cause, intentionality, and mortality. Literature on adolescent development was used to parameterize variables, and Akaike information criteria were used in the final model selections. Findings The trauma registry data indicated a substantial burden of adolescent and young adult injury in both Oman and Kenya, particularly among males. The data indicated significant differences between countries (P .001) in age category, gender distributions, level of education, occupation, cause of injury, and place where injury occurred. Consistent with other literature, road traffic injuries emerged as the most common type of injury as well as the most severe and fatal, with interpersonal violence also resulting in severe injury across contexts. Both road traffic injuries and interpersonal violence were more common among older adolescents and young adults. Education and being in school were protective against injury, after controlling for gender, age category, occupation, and country. Conclusions A rising burden of injuries among young people has been documented in every region of the world, irrespective on income status or level of development. Cost-effective injury control measures targeting this age group exist, including involvement in educational, vocational, and other prosocial activities; environmental alterations; and road safety measures.