Fusing is a process of attaching an interlining like polyester or non-woven material to parts of a garment that require stiffness, such as collars, cuffs, and waistbands. It involves applying a thermoplastic resin to the interlining using various coating methods. The resin is activated by heat and pressure during the fusing process to bond the interlining to the garment fabric. Common fusing methods include flat bed presses, continuous fusing machines, and high frequency equipment. Quality control measures include temperature testing and peel strength tests.