This position paper replaces the 2006 WHO position paper on diphtheria vaccine. It incorporates recent evidence on diphtheria and provides revised recommendations on the optimal number of doses and timing of diphtheria vaccination. In view of the widespread use of combination vaccines, it provides guidance on the alignment of vaccination schedules for different antigens included in routine childhood immunization programmes. The recommendations concerning diphtheria vaccine booster doses later in life are also updated. Recommendations on the use of diphtheria vaccines were discussed by SAGE in April 2017.