The influence of fiber breakage on measurable length properties of cotton and resultant yarn strength was investigated by artificially inducing various levels of damage as experimental treatments upon reference cottons. Some of these materials were prepared in sufficient quantity to allow pilot spinning studies for yarn properties (reported separately). The degree of damage was indexed by the Quality Factor or "Q" statistic (mass fraction of unbroken fibers). It was found that the theoretically predicted response of length parameters to breaking damage differed depending upon whether the effective breaking gage length (spacing between successive breaks) was: (1) fixed or random; (2) greater or less than the length of the longest fibers in the distribution; and: (3) a function of the length of an individual fiber being broken. The experimental data available to date have been consistent with these predictions.