All roads lead to the ring (peripherique) around Brussels. Once you're on the ring, you'll need additional directions to get where you are going.
Coming From Paris
Paris is a three-hour drive to Brussels. Take the A1 out of Paris and it's a pretty straight shot to Brussels. Continue north, merge onto the A2 toward Bruxelles, which then turns into the E19. This takes you right to the ring (peripherique) around Brussels.
At this point, to get to where you want to go, you'll need to enter your GPS coordinates or use a map of Brussels.
Coming from the United Kingdom
Getting to Brussels from the United Kingdom is trickier than coming from Paris - because of that little body of water known as the English Channel. Although a number of swimmers have braved the chilly waters to cross the channel, so far, no car has ever made it over by itself so you'll have to take a ferry from Dover to Calais or come under the channel using the chunnel train.
Once you're in Calais (France), you'll get on the A216 toward St. Omer/Arras/Reims/Paris/Dunkerque/Lille. Keep left toward Dunkerque/Lille and then take the A16 into Belgium. The A16 becomes the E40 which brings you to the ring.
At this point, you'll need to plug in your GPS coordinates or use a map of Brussels
Coming from Luxembourg
To get to Brussels from Luxembourg or eastern France, you'll need to take the E25, merge onto the A6 which then becomes the E411. That will get you to the ring (peripherique) around Brussels.
At this point, to get to where you want to go, you'll need to enter your GPS coordinatesor use a map of Brussels.
Coming from Amsterdam
Although it's pretty much a straight shot from Amsterdam to Brussels by car, the directions are complicated by the fact that you have to wiggle around Breda (NL) and Antwerp (BE). Not difficult to do but I won't complicate matters by trying to explain it simply. Best thing: put the coordinates in your GPS, use a map or www.mappy.com
What I will say about Amsterdam is that driving to and from this city can take longer than you think it should, primarily because the highways just can't handle the large amount of traffic from cars and trucks. So, plan extra time to get to and from Amsterdam.