Accounting software for the oil, gas, petroleum and energy industry. Complete seamless integration into Microsoft Windows applications.

Quality Consulting and Engineering Services for the Oil & Gas Industry. Specializing in cryogenic natural gas liquids recovery, sulfur recovery, and sour gas processing.

Questa Software Systems provides oil and gas industry software in the areas of accounting, revenue, and more.

Clayton Williams Energy, Inc.

Tobosa Exploration, Inc - oil and gas consulting services, reservoir engineering, property appraisals, and geology.