This paper presents a case study of a technical and organizational innovation in a large international infrastructure project. Originally, the research aimed at identifying how cultural diversity affects innovation in project management since literature provides contradictory results. On the one hand, research asserts that cultural diversity is fostering creativity and therefore new combinations of ideas leading to innovations (Gavetti, 2005; Cornet and Warland, 2008; Stalh et al. 2010). On the other hand, research has also shown that cultural diversity hampers collective work since mutual understanding is affected by different communication codes (Hall and Hall, 1990) and languages (Lauring and Klitmøller, 2015), learning processes are slowed down (Gibson and Vermeulen, 2003) and the social cohesion of the team tends to decrease (Staples and Zhao, 2006). All these hurdles may prevent potential innovations from being achieved. To go beyond the contradictory effects of cultural diversity on innovation, this research was designed to look closely at mechanisms fostering or hampering innovation processes.