The generic drug contains the same active substance asthe referenced original drug, in the same dose, in the same or similarpharmaceutical form and can be produced after the patent protectionperiod of the original drug expires. With "The Drug Price Competi tion and Patent Term Restoration Act", informally known as the“Hatch-Waxman Act” in 1984, the requirement for pre-clinical andclinical phase studies was abolished in the approval process of gener ics. In this context, replacement of the former process with the "ab breviated new drug application" has streamlined the widespread useof generics. Generic drug is deemed as therapeutically equivalent toreference product by demonstrating bioequivalence through bioavail ability/bioequivalence studies conducted with a limited number ofhealthy volunteers. Therefore, generic drugs introduced to the marketwith lower costs are generally cheaper than reference drugs. In thisway, generic drugs make a critical contribution to reducing drug ex penditures without conceding healthcare quality. In fact, especiallyin developed countries, it was aimed to off-load the pressure causedby drug costs on the health budget via increasing the use of genericdrugs, and special policies have been implemented. Apart from ad ministrative policies, many factors including consumers’, pharma cists’, and physicians’ perceptions and behaviors about generics,diagnosis and drug-related characteristics, etc. can impact in spread ing the use of generic drugs. In this review, it was aimed to providefundamental information about generic drugs and present the devel opments in the world and in Turkey for these drugs which are be coming more widespread.