People, often from marginalised groups, are trained to conduct detailed interviews with others in their social network, through a process where they are supported in designing interviews and collecting and analysing data. The approach offers a rapid way of gaining in-depth understanding, particularly of sensitive issues such as reproductive and sexual health, and among excluded groups. The PEER process enables programmes to engage communities in dialogue, and promotes the voice of marginalised and excluded groups.

PEER has now been used in the UK among a variety of excluded groups, including young people of Somali descent living in London (funded by the East London Alliance), as part of research into survival strategies of destitute asylum seekers (with the University of Swansea, funded by Oxfam Cymru), and as part of an independent method for evaluation for the Tackling Female Genital Mutliation Initiative for three organisations (Trust for London, Esmee Fairbairn Foundation and Rosa).