Teamwork is defined as a group of people working together towards a common goal, with each person prioritizing the team's success over individual interests. Effective teamwork occurs when members harmonize their contributions. Key characteristics of effective teams include having a clear goal, competent members, unified commitment, and principled leadership. Building a high-performing team is a process that involves distinct stages of forming, storming, norming, and performing, and requires teamwork as an essential component of any major collaborative effort.