| Business | Phone |
| Adm Design Svc 1900 E Eldorado St, Decatur 62521 | (217) 429-4412 |
| Allen Engineering Corp 3848 E Fulton Ave, Decatur 62521 | (217) 428-0566 |
| Blank Wesselink Cook & Assoc 2623 E Pershing Rd, Decatur 62526 | (217) 428-0973 |
| Cochran Engineering 2602 N Morgan St, Decatur 62526 | (217) 875-3333 |
| Process Control & Electrical 2926 N 26th St, Decatur 62526 | (217) 429-4471 |
| Experitec 2241 E Hubbard Ave, Decatur 62526 | (217) 877-5252 |
| Lasater Engineering Ltd 2121 S Imboden Ct, Decatur 62521 | (217) 425-1942 |