Despite the growing emergence of information technology interruptions–those interruptions that are mediated or induced by information technology–little is known about their nature and their consequences on performance. This paper develops a taxonomy of information technology interruptions and presents propositions that relate distinct interruption types and subtypes to individual performance in project environments. A qualitative inquiry of product development teams is used to deductively validate the taxonomy and propositions, and to develop new insights based on an inductive analysis. The paper contributes to research by developing a conceptualization of information technology interruptions in the context of individuals working on interdependent tasks that are nested in related projects. Also, it shows how distinct types of information technology interruptions exhibit differential effects on performance that vary from positive to negative.