This paper evaluates the impact of varying implementation of electronic lab order entry management (eLAB) system strategies on hospitals' productivity in the short run. Using the American Hospital Association's Annual Surveys for 2005-2008, we developed hospital productivity measures to assess facilities' relative performances upon implementing eLAB systems. The results indicate that different eLAB system implementation strategies were systematically related to changes in hospitals' relative productivity levels over the years studied. Hospitals that partially implemented an eLAB system without completing the roll-out experienced negative impacts on productivity. The greatest loss in short-term productivity was experienced by facilities that moved from having no eLAB system to a complete implantation in one year - a strategy called the "Big Bang". The hybrid approach of a limited introduction in one period followed by complete roll-out in the next year was the only eLAB system implementation strategy associated with significant productivity gains. Our findings support a very specific strategy for eLAB system implementation where facilities began with a one-year pilot program immediately followed by an organization-wide implementation effort in the next period. © 2012 Elsevier Ltd.