Few companies own all the resources or perform all the activities described by their business models. Rather, they extend their own capabilities by relying on other firms to furnish particular resources or perform certain activities. Such partnerships can be motivated by needs to acquire knowledge, licenses, or access to customers. A mobile phone manufacturer, for example, may license an operating system for its handsets rather than developing one in-house. An insurer may choose to rely on independent brokers to sell its policies rather than develop its own sales force.