Successful pairings of creative and business minds have been pivotal to some of the most significant brands of our time. Think Christopher Bailey and Angela Ahrendts at Burberry, Marc Jacobs and Robert Duffy at Marc Jacobs International, and Charlotte Tilbury and Demetra Pinsent at Charlotte Tilbury Beauty. Here, beauty execs discuss how to effectively marry entrepreneurial enthusiasm with operational expertise, from dealing with power struggles to recognizing distribution opportunities. An important lesson? Defining clear roles and carving out who owns what function is essential to ensuring positive relationships between members of the executive team.