| # | Company name | Role | # of projects |
|---|---|---|---|
| 1 | Zahl-Ford Inc. | Structural engineering | 1 |
| 2 | Zaldastani Associates, Inc. | Structural engineering | 4 |
| 3 | Zamora Engineering Inc. | Structural engineering | 40 |
| 4 | Zangrilli Engineering | Structural engineering | 2 |
| 5 | Zaralsky Consulting Structural Engineers Ltd. | Structural engineering | 1 |
| 6 | Zaremba-Sopko Associates PLLC | Structural engineering | 3 |
| 7 | Zbigniew Chlebowski | Structural engineering | 1 |
| 8 | Zehner & Bouchon Consulting Engineers Inc. | Structural engineering | 14 |
| 9 | Zelner Socoloske | Structural engineering | 1 |
| 10 | Zemler + Raunicher | Structural engineering | 1 |
| 11 | Zevco Inc | Structural engineering | 0 |
| 12 | ZFA Structural Engineers | Structural engineering | 41 |
| 13 | Zfa Structural Engineers | Structural engineering | 8 |
| 14 | Zhejiang Zhongyuan Curtain Wall Decoration Group Co., Ltd | Structural engineering | 4 |
| 15 | Ziaul Huq | Structural engineering | 1 |
| 16 | Zijderveld Engineers | Structural engineering | 0 |
| 17 | Zinser Engineering | Structural engineering | 0 |
| 18 | Zinser Grossman Engineers | Structural engineering | 6 |
| 19 | ZPF Ingenieure AG Basel | Structural engineering | 10 |
| 20 | Züblin Technisches Büro Konstruktiver Ingenieurbau | Structural engineering | 0 |