This article reviews the emerging literature on developmental relationships and proposes a typology of relationships. Developmental relationships are defined as either formal or informal relationships where an individual takes an active interest in and initiates actions to advance the development of another. The authors focus on five dimensions of developmental relationships: type, network effect, object of learning, time span of outcomes, and developer style. The authors propose four developmental relationship types: organizational navigator, sponsor of development, grandparent, and friend. The authors also identify implications of their typology for both research and practice. (Contains 1 figure.)