The Washington Business Journal annually ranks the 50 fastest growing companies located in the Washington, D.C., area. In 2011, 32 of the Fast 50 firms were based in Fairfax County.
| 2 | Human Touch |
| 3 | MicroTech |
| 5 | Octo Consulting |
| 7 | Evolvent Technologies Inc. |
| 9 | XL Inc. |
| 10 | Invertix Corp. |
| 11 | Solutions Made Simple Inc. |
| 12 | Agilex Technologies Inc. |
| 14 | A-T Solutions Inc. |
| 15 | Suntiva |
| 16 | Data Tactics Corp. |
| 17 | Kingfisher Systems Inc. |
| 19 | Five Guys Enterprises LLC |
| 20 | Carahsoft Technology Corp. |
| 21 | GeoEye Inc. |
| 22 | CPS Professional Services LLC |
| 23 | Zenetex LLC |
| 25 | Blue Canopy Group LLC |
| 26 | Primatics Financial LLC |
| 28 | Building Infrastructure Group Inc. |
| 29 | Triton Security Inc. |
| 30 | immixGroup Inc. |
| 33 | 5 AM Solutions Inc. |
| 34 | MetroStar Systems |
| 35 | Ace Info Solutions Inc. |
| 38 | Pragmatics Inc. |
| 41 | K12 Inc. |
| 42 | M.C. Dean Inc. |
| 48 | DLT Solutions |
| 49 | Guident Technologies Inc. |
| 50 | Celerity |