| Business | Phone |
| A C Nielsen Of Canada 160 Mcnabb St, Markham L3R 4B8 | (905) 475-3344 |
| Analysis Consulting Canada Ltd 80 Acadia Ave, Markham L3R 9V1 | (905) 415-2218 |
| Nielsen Media Research 160 Mcnabb St, Markham L3R 4B8 | (905) 475-9595 |
| D V Research 8901 Woodbine Ave, Markham L3R 9Y4 | (905) 513-7413 |
| Rotenberg Research 110 Riviera Dr, Markham L3R 5M1 | (905) 479-2704 |
| Sampling Modelling Technologie 327 Renfrew Dr, Markham L3R 9S8 | (905) 474-5271 |
| Canadian Inter-Mark Ltd Po Box 26567 Rpo Markville, Markham L3R 0M4 | (905) 479-3791 |
| Drug Intelligence 445 Apple Creek Blvd, Markham L3R 9X7 | (905) 415-8051 |