At the centre of the HIV/AIDS response are the 12 million people who need care and treatment. Those who are ill require support from carers who provide physical, social and psychological support. Yet these carers - essential actors in the response - are often invisible to the system that relies on them. The writers argue that focusing on the carer, at the household level, directs assistance where it is most effective and most needed, will respect human rights, and will help achieve the millennium development goals in health.