Teams are formed to create collective knowledge that leads to higher quality results than would not be possible without teamwork. Who is on the team and why they are on the team is an important consideration in developing a selection strategies. When a strong team is formed they have the ability to master serious challenges within their core competencies.
Within any team there are two major considerations, or circles of influence. There are people that have specific knowledge needed to complete the job effectively that constitute the core group and then there are those added to enhance the end product. Therefore groups have essential members and quality control members.
Essential members might be the people needed as a minimum to complete a project. There could be the designer, marketer, accountant, and operations manager. Without core members the project would never get off the ground as the essential skills and knowledge would not be present.
Beyond the core group there are people who have the capacity to enhance the quality of the outcomes. They may have specific knowledge of core customer demographics, may be design experts that can make the product more user friendly, or could have comparable knowledge of the market.