Optical microscopy, dimensional measurements, and water and hexadecane retention determine the effects of liquid swelling on the structural rearrangement of lyocell twill fabrics. Lyocell fibers swelled 30 percent laterally in water. Laterial swelling in sodium hydroxide increased 200 percent at optimal concentrations. Lateral expanison in the lyocell fibers increased fabric shrinkage and was responsible for most of the irreversible constructional changes occurring during tensioned preparation from the loom state. Swelling-shrinkage and hygral expansion-contraction models explained fabric structural changes occurring during subsequent rewetting resulted in reversible fabric growth. Subsequent rewetting of fabrics prepared in water resulted in reversible shrinkage. Fabrics treated with sodium hydroxide exhibited lower wet state rigidity than fabrics treated with water. Using tension during sodium hydroxide treatment rendered the fabric dimensions more stable to wet and dry cycling. 22 refs.