Over the past two decades, it was largely recognized in the literature that youth programs and interventions would have limited impact if they mainly focused on risks and vulnerabilities. Strength-based approaches have been found to be empowering and effective in various contexts and the interest in preventing youth problems and promoting healthy youth development has led practitioners, policy makers and researchers to develop a wide range of approaches drawn from several theoretical frameworks. Contemporary models of youth development and problem prevention can be generally grouped into one of three types: prevention, resilience, and positive youth development. Each approach gives a unique contribution to the knowledge on coping, development, human adaptation, and thriving, and they all share several key features and a common vision focused on improving the life of youths. Furthermore, models focusing on Positive Youth Development (PYD) pointed out that “PYD” means either developmental processes, or a philosophy to address young people thriving or, finally, the development of programs promoting healthy and positive development in youth. Yet, links and synergies are missing among these three perspectives. More recently, integrative models were developed, having the potential benefit of interconnectedness of risk, protection and assets, within the ecological systems affecting human development, and highlighting the role and the power of the ecosystems in the possibility of change, thus increasing health and well-being, the sense of purpose, fulfillment and thriving. Furthermore, in a period of rapid changes, being happy and not feeling “irrelevant” has to do with being able to deal with diversity and change, maintaining and developing curiosity, and openness to changes and psychological flexibility, thus considering change and diversity as opportunities. The purpose of the present work is to give a guided tour around theoretical frameworks and research that ground this conceptual historical development.