Even though my English and German language skills are at near-native level, for reasons of quality assurance I only offer proofreading and editing of texts written in Dutch, my mothertongue.
Should you need proofreading or editing of an English or German text, I would be happy to refer you to one of my native-speaker colleagues.
A good place to start would be the VZV translator database, or feel free to contact me by either e-mail or telephone at +31 6 52293818.