Trends in fiber quality of United States (U.S.) Upland cotton (Gossypium hirsutum L.) recently have been positive for the three major traits of length, strength, and micronaire. From 1980 to 2010, micronaire trended upward, but it was not highly significant; emphasis on lint yield tends to result in higher micronaire fibers. Fiber strength continues to improve despite a respite in the late 1990s when transgenic cultivars first came on the market. Much of this improvement in fiber strength can be traced back to the New Mexico State University breeding program and its impact on the cultivar Deltapine 90 which is found in many of the improved cultivars. There was one case of possible transgressive segregation for fiber strength in 2006. Fiber length trended upwards until 1997, and then declined until 2006 when it began another period of improvement that currently continues in the U.S. cotton crop. Much of the improvement in fiber length in recent years can be attributed to the introduction of Australian breeding materials into FiberMax and Deltapine cultivars. Pedigree analyses only reveals that Deltapine 90 is in the background of this genetic material, thus much of the improvement in fiber quality over these years can be traced to material developed at New Mexico State University.