With the increased use of harvest aids on the High Plains, a region that has historically grown its own planting seed, concern has been raised regarding the effect of harvest aid chemicals and timing of application on planting seed quality. Harvest aid usage has recently expanded from less than 30 percent of the acres treated in 1992 with up to 80 percent treated in 1995. Harvest aid chemicals are now a very important management tool for High Plains cotton growers. Both growers and seed producers must be able to capture the maximum potential of their crop and not be at the mercy of the weather. Effects of harvest aid treatment on seed quality are important considerations for those who produce seed for next year's crop. The objective of this research is to evaluate the effects of harvest-aid treatments applied at various stages of boll opening on lint and seed yields, fiber properties, and seed quality parameters.