The article explores how companies decide on the limits of their operations, focusing on vertical boundaries. Instead of only considering investments and contracts, they look at how a company's skills and interactions with other groups affect its borders. By analyzing both direct and indirect skills and their relationship with external partners, like suppliers, the study reveals that a company's borders change based on its abilities and its access to outside talents. Essentially, a company's borders are shaped by how it deals with other players and the skills available in the larger business environment.