The Sales office is located in Prague, with a small Dev department. Most R&D is in St. Petersburg and in Munich.
The trick is always the same, when you use english as the common language in your company, you immediately give a strong communication power to native english speakers, they always look so confident when they speak. They look more professional by not doing mistakes, by using a wide vocabulary and by mastering the corporate lingo. That's a place where Europe could innovate: finding a third way between using English that completely obliterate non-native speakers in arguments and using hundred of translators, one for each couple of languages.
Imagine they would be a vast minority, that most of them would be struggling to make a sentence, and that sentence would be hard to understand (this problem sometimes arise inside a language with local accents and dialects), how would meetings turn?