Dear Ladies and Gentlemen, Senoras y Senores, dear IFA Colleagues, bienvenidos to the 70th Congress of the International Fiscal Association (IFA) that is to take place in Madrid from 25-30 September 2016. Our main subjects will be (i) Dispute resolution procedures in international tax matters and (ii) The notion of tax and the elimination of international double taxation or double non-taxation. As usual in Madrid, you will find an array of exciting scientific, social and cultural programmes.