The IHP trimester on mathematical aspects of string theory will kick off with a one week long school for graduate students at the CIRM center in Marseille, from April 11th to April 15th. The following three months will be dedicated to topics at the interface between string theory and mathematics. A light schedule of individual lectures and mini-courses will leave plenty of time for discussion. Two mini-conferences are schedule from the 25th to the 27th of April, and the 23rd to the 25th of May. The trimester will culminate in the Strings-Math conference 2016 at the Collège de France.