Sir, it is news to me that ‘it is only within the last few years that some American orthodontists have started to recommend expansion'.1 I was taught how to expand a dental arch (transverse, anterior and posterior expansion) to correct a malocclusion, when I started as a postgraduate orthodontic trainee in 1991. I continued to use expansion in clinical practice, whenever I considered it appropriate for an individual patient. I was also taught, and regularly treated, young people using functional appliances and without requesting removal of premolars. Although I believed and explained to the young people and their parents that orthodontic treatment could straighten the teeth, improve their smile and improve their social wellbeing, I never claimed that, using these techniques, I could consistently and significantly change their skeletal pattern or cure them of breathing difficulties, temporomandibular disorders, wetting the bed or a number of other conditions, which it has been suggested malocclusion can cause.