Despite receiving some criticism in 2005 for his "hard-headed" approach, Kolles kept his position Managing Director of the team, presiding over the launch of the Midland M16 chassis before the 2006 season began. Following the team's takeover by Spyker and then Force India, he remained as managing director.
Despite running a Formula One team, Kolles has still been called upon to use his dentistry skills. Before the 2005 Turkish Grand Prix, he was forced to perform dental surgery on his driver Tiago Monteiro, who was suffering from toothache that was severe enough to potentially keep him out of the race. He also performed a similar procedure on Midland's other driver Christijan Albers at the 2006 French Grand Prix.
In November 2008, it was announced that Force India chairman Vijay Mallya was to take over the role of Team Principal for 2009, leaving Kolles without a major role in the team. He remained contracted to the team until 31 October 2009, when he resigned as a director.