Over the years HTS has established lasting relationships with international and national energy companies,  as well as major international companies in related sectors.

3M Co.
Dupont
Kellogg/Brown & Root
San Francisco P.U.C.
ABB Lummus
Elliott
Kennicott
Scientific Design
Alfa Laval
ExxonMobil
Kvaerner
Shaw Group
A.G.I.P.
Flowserve
L.A. Water Co.
Shell Co.
Arco
General Motors
Medtronic
Siemens Corporation
Burns & McDonnell
G. J. Oliver
Mitsubishi Industries
Sirrene Engineers
BP America
Gulf Oil
Monsanto
Solar Turbine
Caltex Petroleum
Graver Waters
Northern Natural Gas
Stone & Webster
Carmel Olefins, Israel
Husky Oil Co.
Occidental Petroleum
Sun Oil Corporation
Cameron (NATCO)
Immingham CHP, UK.
Parsons
Syncrude
CBI Howe-Baker
Imperial Oil Co.
Pertamina
Technip
Conoco Phillips
Internorth
PCS Nitrogen
Time-Titanium Metals
Chevron Texaco
Israel Chemical Projects
Pona Engineering
US Borax
Coastal
Jacob Engineering Group
Raytheon Co.
Universal Oil Products