| Client name | City | Country |
|---|---|---|
| Hochschule Mannheim | Mannheim | Germany |
| Hochschule Merseburg (FH) | Merseburg | Germany |
| HOERBIGER Automatisierungstechnik GmbH | Schongau | Germany |
| Holborn Europa Raffinerie GmbH | Hamburg | Germany |
| Holter Regelarmaturen GmbH & Co KG | Schloß Holte-Stukenbrock | Germany |
| Honeywell Austria GmbH | Wien | Austria |
| Honeywell Gas Technolgies GmbH | Kassel | Germany |
| Honeywell Safety Management Systems GmbH | Mannheim | Germany |
| Honeywell UOP | Antwerpen 3 | Belgium |
| Honeywell UOP India Private Limited | Gurgaon Haryana | India |
| HPCL-Mittal Energy Limited | Bhatinda | India |
| hte GmbH | Heidelberg | Germany |
| HTWS Zittau-Görlitz | Zittau | Germany |
| Hualu Engineering company | Xi'an | China |
| Hüttenwerke Krupp Mannesmann GmbH | Duisburg | Germany |
| HWFB Systemtechnik GmbH | Oststeinbek | Germany |
| Hyper Valves Pvt. Ltd. | Ahmedabad | India |
| HYXO OY | Kerava | Finland |
| I.E.C. Dagro B.V. | Sittard | Netherlands |
| I.N.T. S.r.l. - Instrumentation New Technologies | Castelverde | Italy |
| IBB Informationssysteme Beratungs | Neu-Isenburg | Germany |
| Iberoplan S.A. | Madrid | Spain |
| IBF | Bruckmühl | Germany |
| ICIG Business Services GmbH & Co. KG | Wuppertal | Germany |
| IEMA Automationstechnik GmbH | Weißkirchen | Austria |