In paediatric medicine, drug doses are usually calculated individually based on the patient's age, weight and clinical condition. Therefore, there are increased opportunities for, and a relatively high risk of, dosing errors in this setting. Consequently, a systematic literature review using several databases was conducted to investigate the incidence and nature of dosing errors in children; 16 studies were found to be relevant. Eleven of the 16 studies found that dosing errors are the most common type of medication error, three of the remaining studies found it to be the second most common type. This review of published research on medication errors therefore suggests that dosing errors are probably the most common type of error in the paediatric population. In addition, there was a great variation in the error rates reported; this is likely to be due to the differences in the medication error definitions and methodologies employed. For example, the dosing error rate determined using spontaneous reporting ranges from 0.03 per 100 admissions in the UK to 2 per 100 admissions in the US. Extrapolating this, if the under-reporting rate is about 1 in 100, then the true incidence would be around 50,000 paediatric dosing errors per year in England. The information available shows that dosing errors are not uncommon and that 10-fold overdoses caused by calculation errors have led to serious consequences. There is an urgent need to develop methods to reduce medication errors in children and dosing errors should be the first priority.