| Business | Phone |
| 21st Group Inc 9000 Terrace Pl, Des Plaines 60016 | (847) 298-6999 |
| Ajilon Consulting 5600 N River Rd, Des Plaines 60018 | (630) 467-0800 |
| Catena Computers Inc 2350 Bellaire Ct, Des Plaines 60016 | (847) 686-2200 |
| Esco Associates Inc 3166 S River Rd 21, Des Plaines 60018 | (847) 298-5310 |
| Computer Analytics Corp 1011 E Touhy Ave # 170, Des Plaines 60018 | (847) 297-5290 |
| Computer Horizons Corp 6400 Shafer Ct 600, Des Plaines 60018 | (847) 698-6800 |