The modern phenomenon of "startup" has become a highly debated issue in the business world today. Start-ups are small starting companies with an innovative idea, but often their big problem is their funding and a well-chosen business strategy. However, foreign and domestic literature does not offer extensive knowledge of business strategies for start-ups. In view of this fact, we point out the factors influencing the development and functioning of start-up business strategies, and we emphasize the types of business strategies already known in the literature that could be applicable to start-ups as well. However, these are the types of strategies for small or emerging companies. For this reason, we have opted to choose the factors of the external and internal business environment that are complex and variable. Through rating scales, we identify the level at which the parameter that affects the business strategy is being located. We deduce how the average Slovak start-up looks like. If start-ups can identify their business strategy at the beginning of their business, they will advance in the coming years, and their competitive advantages will be sustainable in the long run. A competitive advantage is at the heart of business strategies, no matter whether in large, medium, small businesses, or in startups.