Almost 100 years since the discovery of insulin, hypoglycaemia remains a barrier for people with type 1 diabetes to achieve and maintain blood glucose at levels which prevent long-term diabetes-related complications. Although hypoglycaemia is primarily attributable to the limitations of current treatment and defective hormonal counter-regulation in type 1 diabetes, the central role of psycho-behavioural factors in preventing, recognizing and treating hypoglycaemia has been acknowledged since the early 1980s. Over the past 25 years, as documented in the present review, there has been a substantial increase in psycho-behavioural research focused on understanding the experience and impact of hypoglycaemia. The significant contributions have been in understanding the impact of hypoglycaemia on a person's emotional well-being and aspects of life (e.g. sleep, driving, work/social life), identifying modifiable psychological and behavioural risk factors, as well as in developing psycho-behavioural interventions to prevent and better manage (severe) hypoglycaemia. The impact of hypoglycaemia on family members has also been confirmed. Structured diabetes education programmes and psycho-behavioural interventions with a focus on hypoglycaemia have both been shown to be effective in addressing problematic hypoglycaemia. However, the findings have also revealed the complexity of the problem and the need for a personalized approach, taking into account the individual's knowledge of, and emotional/behavioural reactions to hypoglycaemia. Evidence is emerging that people with persistent and recurrent severe hypoglycaemia, characterized by deeply entrenched cognitions and lack of concern around hypoglycaemia, can benefit from tailored cognitive behavioural therapy.