People are doing sports and physical workouts of any sort - not only behind closed doors, as in clubs of any sort or fitness studios, but in increasing numbers at places that are dedicated to the public. Especially in densely populated areas new ways of working out are shaping up, defined as "city sports". This new movement comes in different shapes, each of them having different requirements on how public areas need to be shaped. Using and occupying public space for different varieties of sports is what it then comes down to, and often this reshape of areas is not done top down, but rather bottom up. These two very different approaches of creating change in public areas often create friction. An example for a do it yourself initiative (DIY) is the self-organised skatepark ALM DIY, situated at the area of former northern trainstation in the 2. Viennese district. This initiative targets for changing the public area to their needs in order for enabling individuals to live their sport. Exactly that mission is what creates friction with other interest groups, as it is occupation of public space for a more or less personal goal. Furthermore, their doing may be seen as putting pressure onto the public sector, as their media coverage and public relations initiatives reveals mistakes made by the city-governments responsibles for public sports. When the primary target is offering possibilities for the public to exercise their favourite sport, how can this area of conflict between public sector and DIY initiatives be put aside for the better? Which requests for change to the increased number of popping up DIY initiatives put onto public planning structures? Which chances, as well as risks, do evolve due to this situation - and can they produce additional value for both the society, as a user of outcome, as well as for the public planning process? Those questions shall be answered in this thesis, via literature research, comparing examples of DIY-initiatives with focus on sports as well as interviews with experts when it comes to the actual situation in Vienna.