Donald Tusk once warned, ‘UK leaving could cause destruction of not only the EU but Western political civilisation in its entirety’. He now has to keep Europe's leaders united in negotiations. He will also prepare the draft letter to the 27 states that will be the negotiating guidelines and response to Britain’s Article 50 letter. Others involved: Michel Barnier goes head-to-head with David Davis in tough negotiations. Sabine Weyand, his deputy and a formidable veteran at representing the Commission’s best interests, will not give much ground in trade talks. Didier Seeuws will head negotiating, keeping 27 governments happy and shaping EU / UK future relationships: he is modest and obliging, grasping complex technical issues and political stakes. David Davis, UK Brexit Secretary and a champion of civil liberties, helped to negotiate the Brussels agreements which he is now charged with unpicking. Oliver Robbins is a popular senior EU adviser who may put free movement of people at the heart of negotiations. Tim Barrow, UK ambassador to the EU, knows Brussels corridors and people.