Innovating and optimizing in public organizations : does more become less?

To enhance public service performance (PSP), public organizations are challenged to optimize and innovate their processes, techniques, policies and services. But can public organizations go too far when innovating and optimizing? Based on survey data from Dutch water authorities, we show that optimization initially contributes more to PSP than innovation, but its contribution is curvilinear: the impact of optimization becomes smaller the more optimization is conducted. The relation between innovation and PSP is, however, linear. Based on additional qualitative data, we show that ambidextrous water authorities run less risk of over-optimizing and use integrative strategies to deal with innovation-optimization tensions.