Proton pump inhibitors have dramatically improved the management options available for patients with acid-related disorders. In patients with gastro-oesophageal reflux disease, currently available proton pump inhibitors provide an excellent outcome for the majority; however, they do not provide optimal pH control in many. Proton pump inhibitors co-therapy reduces, but does not eliminate, the risk of gastrointestinal ulcers and complications in patients taking non-steroidal anti-inflammatory drugs, while in patients with upper gastrointestinal bleeding, it may be difficult to reach and maintain the current therapeutic target of intragastric pH of 6-7. This article reviews the effectiveness of current antisecretory therapy in these three acid-related diseases and areas of unmet clinical need. The potential role of a proton pump inhibitor with an extended duration of action and enhanced acid control from a single daily dose, particularly improved control at night, is discussed. Finally, therapy that could be administered without regard to time of day and/or food intake would offer dosing flexibility and thus have a positive effect on patients' compliance.