Globally distributed software development teams face extraordinary communication and coordination problems due to spatial, temporal, and cultural separation between team members. Using the dyadic model of coordination, the paper proposes a coordination index that encapsulates the coordination difficulties in global software development. The coordination index is derived from four other indicescoupling index, need index, effectiveness index, and time-zone index. While a discrete-event simulation model is used to determine the time-zone index for all possible temporal separations, two rounds of questionnaire surveys were administered among researchers and practitioners world-wide to determine the need and the effectiveness indices. The important factors affecting inter-site coordination were shortlisted after the first round. In the second round, weights were assigned to the short-listed factors by making a pair-wise comparison between them. The paper also demonstrates how the coordination index, so derived, can be used for a few project planning decisions.