"I know a smart business decision when I see one - choosing open standards is a very smart business decision indeed," Kroes told a conference in Brussels hosted by OpenForum Europe, an industry body whose members include Microsoft rivals like IBM and Sun Microsystems.
Neelie Kroes, is The European Union competition commissioner.
Open standards allow software companies to develop products that work seamlessly together with those of other companies, according to OpenForum Europe. The open-source movement, which is different, advocates freely sharing the underlying code used for software, the group said.
Though Kroes did not name Microsoft, she made it clear that she meant the software giant when she referred to the only company in EU antitrust enforcement history that has been fined for refusing to comply with European Commission orders - a distinction held by Microsoft.
The EU has ruled against Microsoft for abusing its dominance in the markets for software to play music on computers and to communicate with powerful server computers on a network.
In her speech, Kroes said there were serious security concerns for governments and businesses associated with using a single software supplier. She praised Munich for using software based on open standards, along with the German Foreign Ministry and the Gendarmerie Nationale, a department of the French police force.