Special Envoy of the UN Secretary-General for Yemen, Martin Griffiths, takes us back to the origins of private diplomacy and his early efforts to bring peace to the Indonesian province of Aceh and the Basque region. He talks about the ‘tradecraft’ of starting secret talks and the art of establishing trust with conflict parties. His wealth of experience has taught him invaluable lessons, and he explains how he applies them now, in Yemen – one of the most complex conflicts of our time.