The introduction of proton-pump inhibitors (PPIs) into clinical practice since about thirty years has greatly improved our therapeutic approach to acid-related diseases for their well recognized efficacy and safety. Accordingly, the role of surgery has been enormously reduced in this field. The main indications for PPI use are universally acknowledged by many scientific societies and are the following: treatment of gastroesophageal reflux disease in its various forms and complications, eradication of H. pylori infection in combination with two or more antibiotics, therapy of H. pylori-negative peptic ulcers, healing and prevention of NSAID-associated gastric ulcers, co-therapy with endoscopic procedures to control upper digestive bleeding and medical treatment of Zollinger-Ellison Syndrome. Despite the above well-defined indications, however, the use of PPIs continues to grow every year in both Western and Eastern countries and this phenomenon poses serious queries about the appropriate prescription of these drugs worldwide. In fact, the endless expansion of PPI market has created important problems for many regulatory authorities for two relevant features: the progressive and irreversible increase of the costs of therapy with this class of drugs and the greater potential harms for the patients. So, there is the need for a reappraisal of PPI correct indications for both general practitioners and various specialists in order to re-establish a correct use of these effective drugs in daily clinical practice, according to the best evidence-based guidelines.