Downhole services for completing a well, stimulating a well or working over a well. May involve drill pipe, wireling or coiled tubing.

Includes both oil field "dirt-moving" work such as construction of locations, mud pits, etc. Also includes construction of gas plants and other permanent field facilities.

Companies whose principal business is drilling oil and gas wells, including those who operate entirely offshore.

Includes both suppliers of drilling fluid additives and engineering firms that optimize drilling fluid properties.

These companies repair engines, turbines, pumps, processing gear and other heavy equipment in the field. Many also have a shop where similar repairs are made.

Companies that put out oil field fires and control wells blowing wild. Also includes companies specializing in dealing with H2S and other hazardous substances. Includes firms specializing in safety training for field personnel.

Includes a wide variety of organizations supporting drilling, construction and other oilfield work. Includes marine transportation firms, as well as firms providing temporary housing, food service, etc.

Companies that provide personnel and/or equipment to monitor and describe mud gas and lithology of cuttings during drilling operations. Also may provide other well site services such as supervision of coring operations.

This subcategory is for sites offering pipeline related services.