INTRODUCTION: Gastrointestinal symptoms such as heartburn, indigestion (or dyspepsia), bloating, distension, constipation, abdominal pain, abdominal discomfort and diarrhoea are extremely common worldwide. For some, such symptoms can prove to be chronic and disabling. METHODS: The recent literature on irritable bowel syndrome and, in particular, work emanating form this authors research group, was reviewed. RESULTS: These functional symptoms commonly occur in aggregations, referred to as functional gastrointestinal disorders (FGIDs). Some of the FGIDs and, most notably irritable bowel syndrome (IBS), have achieved a degree of scientific and clinical credibility as coherent entities. Several lines of evidence ranging from gut motility to the microbiota are under investigation in attempts to explain IBS or its symptomatology. CONCLUSION: Though biomarkers for IBS and other FGIDs have proven elusive, considerable progress has been made in understanding possible aetiological factors in IBS; progress which may well lead to better therapeutic strategies.