Technical Abstract: Pima cotton is roller ginned to minimize damage to the fiber. A survey was conducted of 24 US roller gins to better understand how current foreign matter removal practices affect Pima cotton quality. All gins used at least two stages of drying and two-thirds used three stages. For seed-cotton cleaning, all gins used at least one cylinder cleaner; the average number of cylinders was 21. Mostly all of the gins used at least one stick machine, and seven gins used impact cleaners. Most gins used one or two cylinder cleaners along with one air-type lint cleaner for lint cleaning. Some of the gins used impact and mill-type cleaners for lint cleaning. The trend in roller ginning today is towards aggressive seed-cotton cleaning and gentle lint cleaning to limit fiber damage. Cotton property measurements taken before and after cleaning showed that, in general, cleaning machinery reduced foreign matter content in seed cotton and lint, and tended to reduce fiber length and increase neps. There was an average increase in lint value from 75.5 to 78.1 ¢/lb due to lint cleaning. No definite recommendations for foreign matter removal at US roller gins could be made, but the results emphasized the need for future Pima cleaning research.