From the "700 year" (Big C- Hang Dong) ring road on the south side of Chiang Mai, turn south on the river road on the west side of the river. (Opposite side of the river from McKean hospital)) Drive south for one kilometer. When the river bends to the left you will be at a four way intersection (right after the 7-11.) Go straight through the intersection.
Stay on this road for 400 meters. It will turn left and then right. As you cross the second small bridge you will see a bright green building in front of you. We are across the street from the green building. Go straight after you across the bridge for about 50 meters. The parking lot is in the back of the building. The entrance gate is on the right.
Note: The red flag on the map is the location of the office. If you click on it you can generate driving directions from where you are located.