Garment construction is based on converting a fashion fabric into a wearable structure. Interfacings are attached to the fashion fabric in enclosed seams to provide support and stiffness for the seam area. Interfacings affect how the fashion fabric can bend. Therefore, it is the purpose of this study to determine the effect fusible and nonfusible nonwoven interfacings have on three bending properties of a lightweight suiting fabric. These three properties are flexural rigidity, crease recovery, and seam head size. A lightweight suiting fabric, a nonwoven fusible interfacing, and a nonwoven nonfusible interfacing were selected for the study. The flexural rigidity and crease recovery were measured for the component pieces of fashion fabric, nonfusible interfacing, and fusible interfacing and for the fusible and nonfusible composites. The flexural rigidity and crease recovery for the composites were recorded for the composite bent with the interfacing side up and with the interfacing side down. Seam head size was measured for enclosed seams with no interfacing (control), fusible interfacing, and nonfusible interfacing. Cross-sections of the enclosed seams were photographed against a ruler with hundredths of an inch increments. The seam head size was read from each of the photographic slides. Seven null hypotheses were tested. The hypotheses pertained to bending resistance and crease recovery of composites and their components, interfacing side up and down when bending and creasing, and fusible and nonfusible composites; and to seam head sizes of composites of the three selected fabrics. It was found that it did not make a difference which interfacing type is used (fusible or nonfusible) with respect to crease recovery and seam head size. It did make a difference which interfacing type was used with respect to flexural rigidity. The fusible composite was 2. 47 times stiffer than the nonfusible, however. / Master of Science