A comparison of bleaching processes used samples of wool, wool-cotton blends, and 100% cotton fabrics. The bleaching processes varied relative to the concentration of hydrogen peroxide, the time, the use of thiourea dioxide, the number of stages, and the number of baths. Measurements of photoyellowing and phototendering in the samples followed exposure to artificial sunlight. Photoyellowing was similar in all samples. Strength loss was greater in samples processed by conventional hydrogen peroxide bleaching than those processed by two-stage, single bath, sequential oxidative/reductive bleaching. In full bleaching processes, the reductive stage contributed significantly to strength loss, which was compensated by the oxidative stage. Whiteness and yellowness values for wool were similar with all processes.