| Business | Phone |
| Aventec Inc 60 Centurian Dr, Markham | (905) 305-1711 |
| Alston Associates Inc 60 Bullock Dr, Markham L3P 3P2 | (905) 294-0039 |
| B J Tworzyanski Ltd 7291 Victoria Park Ave, Markham L3R 3A4 | (905) 946-8686 |
| Goel Group Ltd 500 Alden Rd #202, Markham L3R 5H5 | (905) 475-8849 |
| Hma Consulting Inc 7240 Woodbine Ave, Markham L3R 1A4 | (905) 474-2431 |
| John Towle Assoc Ltd 665 Hood Rd, Markham L3R 4E1 | (905) 475-8705 |
| Lea Consulting Ltd 625 Cochrane Dr, Markham L3R 9R9 | (905) 470-0015 |
| Lumentech Engineers Inc 550 Alden Rd, Markham L3R 6A8 | (905) 415-0110 |
| Mac Viro Consultants Inc 90 Allstate Pky #600, Markham L3R 6H3 | (905) 475-7270 |
| Ssn & Assoc 174 Trail Ridge Lane, Markham L6C 2C5 | (905) 887-2224 |
| Bmh Systems Inc 215 Shields Crt, Markham L3R 8V2 | (905) 470-8300 |
| Masongsong-Atkari Engineering 1151 Denison St #1, Markham L3R 3Y4 | (905) 944-0162 |
| Murley & Assoc 688 Village Pky, Markham L3R 2Y5 | (905) 475-8057 |
| Pharm Eng Technology Inc 145 Royal Crest Crt, Markham L3R 9Z4 | (905) 415-3955 |
| Process Solutions Intl Inc 18 Crown Steel Dr, Markham L3R 9X8 | (905) 479-6587 |
| Banerjee & Assoc Inc 260 Town Centre Blvd, Markham L3R 8H8 | (905) 470-7600 |
| Schindler Technologies Corp 653 Village Pky, Markham L3R 2R2 | (905) 415-8106 |
| Stantec Consulting Ltd 7270 Woodbine Ave #300, Markham L3R 4B9 | (905) 474-0455 |
| Team Associates Ltd 3950 14th Ave, Markham L3R 0A9 | (905) 947-8266 |
| Toronto Inspection & Testing 110 Konrad Cres, Markham L3R 9X2 | (905) 940-8509 |
| Trow Consulting Engineers Ltd 70 Gibson Dr, Markham L3R 4C2 | (905) 470-0073 |
| Fault Detection & Control 20 Ellingwood Crt, Markham L3R 8A8 | (905) 940-1859 |
| Wilson S S & Assoc 25 Valleywood Dr, Markham L3R 5L9 | (905) 940-1363 |
| Zaretsky Consulting Structural 25 Valleywood Dr, Markham L3R 5L9 | (905) 470-1080 |
| C & V Engineering 33 Ferrier St, Markham L3R 3K6 | (905) 477-7525 |
| Calearth International Dev 7270 Woodbine Ave, Markham L3R 4B9 | (905) 415-0500 |
| Cdb Technical Svc Inc 625 Cochrane Dr, Markham L3R 9R9 | (905) 513-1950 |
| Central Projects Group Inc 250 Shields Crt #15, Markham L3R 9W7 | (905) 470-6570 |
| Chih S Huang & Assoc Inc 2750 14th Ave #11, Markham L3R 0B6 | (905) 475-0784 |
| Chisholm Fleming & Assoc 317 Renfrew Dr, Markham L3R 9S8 | (905) 474-1458 |
| David Schaeffer Engineering 600 Alden Rd #209, Markham L3R 0E7 | (905) 475-3080 |
| Dba Engineering Ltd 370 Steelcase Rd E #A, Markham L3R 1G2 | (905) 940-8383 |
| Digital Climate Ltd 570 Alden Rd, Markham L3R 8N5 | (905) 474-3334 |
| E C & Assoc Ltd 80 Acadia Ave #303, Markham L3R 9V1 | (905) 477-9377 |
| Dyche Engineering Inc 50 Acadia Ave, Markham L3R 0B3 | (905) 946-8262 |
| E D Roberts & Assoc Ltd 461 Alden Rd, Markham L3R 3L4 | (905) 470-7404 |
| Ellco Enterprises 50 Ramona Blvd, Markham L3P 2K3 | (905) 294-8916 |
| Ellard-Wilson Engineering Ltd 260 Town Centre Blvd, Markham L3R 8H8 | (905) 940-3100 |
| Geo-Canada Ltd 90 Nolan Crt, Markham L3R 4L9 | (905) 474-9255 |