The recommendations in this guidance relate exclusively to studies submitted in support of an abbreviated new drug application (ANDA). This guidance provides recommendations for the design and conduct of studies evaluating the adhesive performance of a transdermal or topical delivery system (collectively referred to as TDS). Depending on the objectives of a TDS product development program, applicants may choose to evaluate TDS adhesion in studies performed to evaluate TDS adhesion only or in studies performed with a combined purpose (e.g., for the simultaneous evaluation of adhesion and bioequivalence (BE) with pharmacokinetic (PK) endpoints).