This cluster of papers focuses on the advances in drug delivery systems, including the use of cyclodextrins, solid dispersions, nanosuspensions, and lipid-based formulations to improve drug solubility and enhance oral delivery. It also explores the application of the Biopharmaceutics Classification System and the development of amorphous pharmaceuticals for improved drug absorption. The research covers a wide range of topics related to pharmaceutical materials and gastrointestinal drug absorption.