In memoriam: Prof. dr. Johannes Jisse Duistermaat#

The staff of the Mathematics Institute of Utrecht University are overwhelmed and saddened by the death of colleague and friend Hans Duistermaat on March 19, 2010.

Hans has occupied the Institute's Chair of Pure and Applied Mathematics since 1974. For the last five years of his career he was an Academy Professor. He was also a Knight of the Order of the Dutch Lion and a Member of the Royal Netherlands Academy of Arts and Sciences, KNAW.

Hans was a passionate researcher of international standing. Again and again he chose to follow new roads. Many, including Ph.D. students, were inspired by his ideas, which he gladly shared. For students, he was accessible and his teaching was characterized by clarity and infectious enthusiasm.

To a great extent, the character of the Institute has been determined by Hans' sparkling personality and great craftsmanship. This leaves us with gratitude.

Our thoughts are with his wife Saskia, his daughters and his extended family.

Hans reached the age of 67.

Prof. dr. Odo Diekmann Department of Mathematics