This article reports the analysis of case studies of portfolio entrepreneurs that suggests that one of the main reasons for the formation and expansion of business groups is the need to create an entrepreneurial team, which is achieved by giving minority shares in the new ventures to others, mainly former employees. This enhances entrepreneurs' ability to grow and diversify the businesses under their control without compromising their ownership control of the overall business group. The article identifies and discusses the different types of entrepreneurial teams developed by portfolio entrepreneurs: joint ventures with established entrepreneurs, employee involvement, and intrapreneurship. The latter two types were specifically interesting in studying situations where there was a dominant entrepreneur and associate entrepreneurs. The article enhances the theoretical and empirical understanding of how growth is achieved in the small firms sector through business group formation, and sheds insights on how entrepreneurial team dynamics operate in multiple business contexts.