||The growing emphasis on teams and groups in knowledge production, combined with women’s educational gains in science and engineering, propel gender diversity to the forefront of promising new opportunities for scientific discovery (Nielsen et al., 2017). Recent studies suggest positive links between gender diversity of teams and collective problem solving (Woolley et al, 2010) as well as effectively using the expertise of each team member (Joshi, 2014). Little is known about the dynamics of group composition within academia. We therefore formulated three research questions: (1) Which percentage of the teams are composed of both male and female scholars?; (2) What are differences between countries and world regions regarding mixed teams?; (3) What are developments over time? In this study we show that all world regions have been gradually increasing over time the share of output of mixed gender teams. EU28 countries outperform in each reported year, from 2009 till 2016, the other world regions. In future studies, which are scheduled in the spring and summer of 2018, we will analyse possible performance differences between the three typologies of teams, homogeneous male teams, homogeneous female teams and heterogeneous (mixed) teams within EU28 countries.