The evolution of alliance portfolios: the case of Unisys

How do alliance portfolios evolve? We develop grounded theory based on Unisys' case, which reveals how exogenous technological changes at the industry level and shifts in a firm's strategy shape the composition of partners and the nature of alliance relationships. We identify four evolutionary processes: responding to external stimuli, breaking off inertial pressures, enabling coevolution, and restructuring and realigning the alliance portfolio. We shift attention from alliance formation decisions to changes in the nature of alliances and partner characteristics throughout the duration of the alliance portfolio. We suggest that the evolution of alliance portfolios cannot be fully explained by path dependence, life-cycle patterns, or proactive design. Instead, alliance portfolios are shaped by environmental stimuli and conflicting organizational processes.