The in vitro release test (IVRT) has been proposed initially for the evaluation of the impact of controlled changes in composition and manufacturing process (scale-up and post approval changes). Gradually, the role of IVRT has been extended by publication of product specific draft guidances (US Food and Drug Administration). It is part of the aggregate weight of evidence approach and it has an assumed ability to reflect in aggregate the influence of several physical and chemical properties. The 2108 Draft guidance on quality and equivalence of topical products published by European Medicine Agency mentions IVRT as required to support the new concept of Extended Pharmaceutical Equivalence. The significance of comparison of in vitro performance depends on adequate understanding of the compared products, characterization of the degree of similarity / differences and evaluation of their impact on the in vivo outcome. The presentation will focus on current applications and trends in IVRT.