The use of polypropylene staple fiber in apparel fabrics has grown, in part, because of improvements in the fiber's properties. The development of fabrics constructed from polypropylene/cotton yarns is in response to consumer demand for fabrics that have improved performance and comfort characteristics. Ideally, fabrics constructed from polypropylene/cotton yarns will contain the light weight, strength, and wicking attributes of polypropylene, and the absorption and dyeability of cotton. Possible end uses for this blend are athletic wear and socks. In this study, a number of ring and rotor yarns were spun from polypropylene and cotton. These included polypropylene/cotton blended yarns (blends of 33/67, 50/50, and 67/33), 100 percent cotton yarns, and 100 percent polypropylene yarns. Two deniers (1.25 and 1.80) and two lengths (25.1millimeters and 32 millimeters) of polypropylene fiber were used. The characteristics of the yarns were documented. Yarns were knit into single jersey fabrics, and fabrics were dyed. The comfort, performance, and aesthetic properties of the knitted fabrics, including air permeability, wickability, hand, pilling, appearance, moisture content, and color depth, were analyzed. General findings were that yarn and fabric strength improved at levels of 50 percent polypropylene and greater. Fabric appearance was preferred as the percent of cotton increased in the blend, and fabrics made from the rotor yarns had a preferred appearance over those made from the ring yarns. The moisture content of the fabrics increased with the reflected the moisture absorption properties of the fibers. 31 refs.