Technological change and advancing digitalization are now indispensable in the fitness and health industry. In addition to an increasing number of increasingly sophisticated high-tech fitness devices, there is also a rapid growth of fitness apps and online platforms. Startups, in particular, play a significant role in the development of technologies and business models in the digital fitness sector. But what factors determine whether a company is successful or not? This book addresses this question. It analyzes existing approaches to secondary success factor research and conducts and evaluates a series of expert interviews, as well as contrasting the results of secondary and primary success factor research, with the aim of uncovering key influencing factors of success. Based on these results.