In todays digitized and globalized economy, many industries simultaneously face increasing competi-tive pressures and unprecedented speed of change in business conditions. As IT budgets are limited, process owners and IT departments need to decide how to divide their spending on efficiency-enhancing and flexibility-enhancing IT capabilities to optimally support the execution of business pro-cesses. Turning from thinking of efficiency and flexibility as trade-off towards ambidexterity puts focus on simultaneously pursuing efficiency through exploitative and flexibility through explorative business process IT (BPIT) capabilities. While these capabilities have been analysed independently, there is scarce research on the combined effects. This gap is addressed by investigating the impact of combin-ing exploitative and explorative BPIT capabilities on business process performance. This is done through a quantitative study in the German utilities sector, which serves as one instance of highly com-petitive and dynamic industries. Distinct combination strategies are identified and a variance-theoretical model is developed, explaining their impact on business process performance. We intend to contribute to the area of business process management (BPM) by showing the importance of balancing efficiency and flexibility for a business process. Furthermore we add to research on ambidexterity in IS by expanding existing work through focussing on the process level.