emergency departments (ed) exist for the purpose of caring for patients with urgent or life-threatening conditions which are time sensitive to treat. ed crowding is a condition where demand for ed services exceed the facility's capability of meeting that demand, and often results in increased wait times for services. this thesis explored the factors related to ed crowding in an academic health sciences centre located in northwestern ontario. predictors of frequent use were also examined, as were potential explanatory variables for an observed 18% increase in ed visits over a 5-year period.