Among the many formulas that exist for financing a business project, two of the most widely used by entrepreneurs today are business angels (BA) and venture capital (VC). This chapter sheds light on the interaction between these sources of funding. Both financing options played an essential role for the growth of start-ups even before the financial crisis. In particular, the main goal of this chapter is to provide the reader with an accurate understanding of both sources of financing before making an investment decision. The chapter shows the concept, operations, and growth expectations of BA and VC and a subsequent comparison between the two methods. Overall, this chapter provides a more fine-grained understanding of the role that BA and VC investors can play in the process of creating new ventures. As the main takeaways of this chapter, it is expected that entrepreneurs will learn to successfully find the financing formula that best suits the characteristics and urgencies of their project and that, in this way, their company will develop or continue to grow.