All effective youth programs have youth development at their core. Effective youth leadership programs build on solid youth development principles, with an emphasis on those areas of development and program components that support youth leadership. This paper has been created by the National Collaborative on Workforce and Disability for Youth (NCWD/Youth) to assist youth service practitioners, administrators, and policymakers in defining, differentiating, and providing youth development and youth leadership programs and activities, which are important components of the Workforce Investment Act (WIA).