The street address is Rue Guimard 9, 1000 Brussels.
The office is located in the European district, not far from the commission (10 minutes’ walk) or the parliament (5 minutes’ walk). The nearest metro station is Arts-Loi, located on lines 2 and 6. When you get out from the metro station, turn right and then right again on the first cross street. Follow the road for a little over a minute and you will see building number 9. The office is located in the intersection between the two roads.
Alternatively, the airport shuttle bus also stops at the junction between Place Luxembourg and Rue de Trèves, in close proximity to the office. You can also take the train to Brus.-Luxemb. station which is located next to the parliament.