Virtual teams are increasingly common in organizations, yet explicit theory and research on virtual team processes and outcomes is relatively rare. In this chapter, we first place virtual teams in context and provide a two dimensional framework for understanding the range of virtualness. We then build from foundations of diversity, psychological safety, social identity, conflict, and transactive memory to provide a coherent model of traditional, hybrid, and virtual team outcomes. Fourteen propositions are derived from these foundations - covering knowledge availability, sharing, refinement, and storage. Teams whose members are separated by geographical or temporal distance can have considerable positive outcomes for organizations, if they are effectively managed and supported.