This collection of essays was prepared to celebrate the 70th birthday of Professor Roland Naul. Book chapters have been written by a range of colleagues and friends from Europe and the rest of the world. Some contributors have been working with Roland Naul in recent years while others accompanied his research projects in previous decades. Taken together, these chapters illustrate the development of sport and physical activity research over four decades, in Germany, Europe, and worldwide. One objective was to give an overview and update of relevant fields that determined the academic work and the research profile of Roland Naul for more than forty years. Another objective was to give new impulses to these fields that will help to face the challenges our changing society is confronted with nowadays. Individual chapters have been grouped under the following aspects: secondary education and vocational training in Germany and Europe, with a focus on sport qualifications and professions--old and new challenges for the Olympic Games movement, as described from the perspective of different countries--health-enhancing physical activity (HEPA), a key policy area which Roland Naul has contributed to shaping in the European Union--the relationship between sport pedagogy and social pedagogy--the well-being of athletes is in the focus, with contributions tackling the prevention of harassment, corruption, match-fixing or doping--and finally, sport policy on a local level, including examples of local multi-actor networks, community-based interventions or the perspective of big cities: another area of policy development to which Roland Naul has made substantial contributions. With all these contributions from former and / or current colleagues of Roland Naul, his outstanding academic work and research in these fields is emphasized. Finally, this commemorative publication aims to acknowledge the merits of Roland Naul for European studies in physical education and youth sports, as well as for the sport policy context in Europe.