Gastric emptying is a complicated process, thus the in vivo performance of drug delivery systems is unknown. Many physiological obstacles including; short gastric residency time (GRT) and variable gastric emptying time (GET), have reduced the efficacy of oral dosage forms. To combat this fickleness, attempts have been undertaken to increase the dosage form's retention time, resulting in the creation of Gastroretentive Drug Delivery Systems (GRDDS). The GRDDS can stay in the stomach for an extended period of time, increasing the gastric residence duration of medications and improving their bioavailability. These are commonly employed in the treatment of gastrointestinal illnesses and disorders for site-specific drug administration. Also, they enhance the absorption of drugs that are only soluble in the stomach. In this review, we will discuss numerous and different techniques for GRDDS such as floating systems, non-floating systems and their sub-types. A list of recent patents on GRDDS is also included, along with a full description of the assessment parameters.