Purpose: To map measures routinely collected in youth mental health services to Quality Adjusted Life Years (QALYs). Type: R package. Release status: Development release. Development releases should be viewed as “experimental” and have yet to complete all of the verification and validation checks expected of production releases. Intended users: Mental health planners and researchers with at least basic skills in using statistical software. Users must have an up to date version of the R statistical software installed on their machine to install and use the youthu R package.