| # | Company name | Role | # of projects |
|---|---|---|---|
| 1 | A R Sparaco | Engineering company | 0 |
| 2 | AA Gonzalez Consulting Engineer | Engineering company | 3 |
| 3 | Abb Randall Engineers/contractors | Engineering company | 0 |
| 4 | Abedini Norris Consulting Inc. | Engineering company | 18 |
| 5 | AC Ingénierie Lorraine | Engineering company | 1 |
| 6 | Acix Consultoría Técnica | Engineering company | 1 |
| 7 | Action Engineering Consultants | Engineering company | 1 |
| 8 | Action Geotechnical Consultants | Engineering company | 0 |
| 9 | Adler Development | Engineering company | 0 |
| 10 | Adler Engineering Inc | Engineering company | 1 |
| 11 | Advanced Storage Technology - Ast | Engineering company | 1 |
| 12 | AE Associates Inc. | Engineering company | 3 |
| 13 | AECOM | Engineering company | 4 |
| 14 | Aerostar SA | Engineering company | 1 |
| 15 | Affiliated Engineers, Inc. | Engineering company | 2 |
| 16 | Affiliated Engineers, Inc. | Engineering company | 1 |
| 17 | Affliated Engineers W, Inc. | Engineering company | 1 |
| 18 | Agra Earth And Environmental Inc. | Engineering company | 3 |
| 19 | Agra Earth Environmental Soil Engineer | Engineering company | 0 |
| 20 | AJW Engineering Ltd. | Engineering company | 5 |