This book provides answers to three questions: (1.) How does our understanding of entrepreneurship change with the new information about business ownership? By utilizing information about all people living in Finland, it is found that entrepreneurship is more prevalent and more important for the growth of prosperity than previously believed based on earlier information compiled on entrepreneurs. (2.) What are typical characteristics of growth-seeking startup companies and how many are founded each year? By analyzing all companies started during one year from this perspective we see, among other things, that startups with great potential are indeed being set up, but ultimately there are rather few of them and most tend to be in the software business. (3.) In what way and over what period of time are the social impacts of growth companies realized? A careful decomposition analysis shows that some of the growing scaleups are also engines of growth in the entire economy, but only through a prolonged, complex and painful mechanism.