Some of the richest helium-bearing gas in the world was produced from fields completed specifically for helium in northeastern Arizona in the 1960s and 1970s. All production came from fields in Apache County (Figure 1). Three fields were located in the Holbrook Basin south of the Defiance uplift about 35 miles northeast of Holbrook. One field was located in the Four Corners area north of the Defiance uplift near the small community of Teec Nos Pos. Helium-rich gas was discovered in the Dineh-bi-Keyah oil field on the northeastern flank of the Defiance uplift in the late 1960s but was not produced until 2003. Helium concentrations range from trace amounts up to 10% in the Holbrook Basin and Four Corners area. Both areas have good potential for additional discovery and production of helium. Helium content in gas is generally considered to be of commercial interest when the concentration is above 0.3% (Casey, 1983, p. 749). Most of the helium produced in the United States is extracted from natural gas from fields in Wyoming, Utah, Colorado, New Mexico, Kansas, Oklahoma, and Texas (Pacheco, 2003, p. 80). The extracted helium is processed into a crude helium product, which varies from 50% to 80% helium, and is ultimately purified to a Grade-A helium product, which is 99.995% or better. Most helium is shipped as a liquid to distribution centers in trucks from where it is sold as bulk liquid helium or gasified and compressed into tanks and small cylinders for delivery to end users. (29 pages)