The purpose of this review on floating and swellable drug delivery systems is to compile the recent literature with special focus on the principal mechanism of floatation to achieve gastric retention. The review also aims to discuss various parameters affecting the behavior of floating and swelling multiparticulate in oral dosage form summarizes the in vitro techniques, in vivo studies to evaluate the performance and application of floating and swellable systems, and applications of these systems. These systems are useful to several problems encountered during the development of a pharmaceutical dosage form. From the formulation and technological point of view, the floating and swellable drug delivery systems are considerably easy and logical approach. An attempt has been made in this review article to introduce the scientists to the current technological developments in floating and swellable drug delivery system.