The term failure to thrive (FTT) can imply very different conditions, depending on the context. To a general paediatrician, it might conjure up a respectably clad child, sitting on an anxious mother's lap as you study growth charts and test results in the hope of inspiration. To a social worker it might imply a wasted, miserable child found in a cold, dirty house. These differing images reflect not just the wide range of children who might receive the label “failure to thrive”, but also a diversity of ideas about what FTT is and how it should be managed. The term was first coined to describe a syndrome of delayed growth and development also called the “maternal deprivation syndrome”.1 Although it is now accepted that FTT has a predominantly nutritional cause,2the implication of an association with emotional and physical deprivation persists. However, all the early studies were of highly selected children, referred to hospital, and it is only in the past 15 years that population based studies have been conducted. What light have these studies shed on the subject and what implications do they have for practice?