Chapter 9 Tensions in Portfolios of Temporary Organisations: How Project Portfolio Maturity Attenuates the Negative Effects of Portfolio Ambidexterity

Portfolios of temporary organisations, particularly portfolios of R&D projects with different project partners, are a common yet understudied phenomenon. We know that these portfolios suffer from tensions inherent in project portfolio ambidexterity (e.g. portfolios balancing R&D projects with new and recurrent partners), yet our understanding of what might lessen these tensions remains limited. This study introduces the idea of project portfolio maturity and theorises how it can mitigate the negative effects of ambidextrous project portfolios. We test our hypotheses by combining proprietary survey and archival data on 136 R&D project portfolios in the German biotechnology industry covering project partnerships with both new and recurrent partners. Our results show that ambidextrous project portfolios hamper firm performance and that portfolio maturity mitigates these negative effects. By introducing a new perspective on project portfolios that accounts for overlooked temporal dimensions, this study provides a new contingency that has the potential to ease the tensions that result from projects with new and recurrent partners. We thereby add to the literatures on temporary organising, project portfolios, and ambidexterity.