Iron deficiency anaemia develops when there is not enough iron in the body to sustain normal red blood cell production. It is a major cause of morbidity worldwide and is linked to a range of comorbid conditions, including gastrointestinal cancer. In the UK, iron deficiency anaemia is the most common cause of anaemia identified in primary care and is estimated to affect 3% of men and 8% of women. Nurses can support the management of iron deficiency anaemia by identifying possible causes, ordering blood tests, advising on diet and iron supplementation, and referring patients for additional investigations as required. This article provides an overview of the pathophysiology, identification and diagnosis of iron deficiency anaemia, describes sources of dietary iron and factors influencing dietary iron absorption, and discusses patient management.