This paper investigates the determinants of the ambition to grow among Dutch early-stage entrepreneurs (nascents and young business owners). We use Adult Population Survey data of the Global Entrepreneurship Monitor (GEM) for the Netherlands. Merging cross-sectional data of the years 2002 to 2007, we arrive at a sample of 409 nascents and 336 young business owners. Growth ambition is measured by asking the respondent which statement fits him or her best: (1) I want my company to be as large as possible, or (2) I want a size I can manage myself or with a few key employees. We find that nascent entrepreneurs and young business owners are equally likely to strive after business growth. For nascent entrepreneurs we find that fear of failure and entrepreneurial self-efficacy are important factors explaining growth ambition. Starting a business because of perceiving and exploiting a business opportunity (as opposed to starting a business out of necessity) is an important driver of growth ambition for both nascents and young business owners, although it is more important for nascents.