This book is a gift from the international community of amyloid friends, presented to Professor Dr. Enno Mandema on the occasion of his retirement from the University of Groningen, the Netherlands. It is the "precipitation" of up to date knowledge of amyloidosis, as presented at the International Course on Amyloidosis in Groningen, on the 10th and 11th of October 1986. Twenty years ago, Professor Mandema invited a group of scientists, who were studying the various aspects of amyloidosis from different points of view, to discuss their mutual interest in the subject. This "First International Symposium" was held for five days in September 1967. It was a wonderful experience for the participants, as most of them had until then only read each others work in the literature. The proceedings of that symposium, which contained the "lively" dis cussions, became a text-book for the following years. Research continued, and while the book was still in preparation, the revolutionary method of "water-soluble amyloid" was published. In the following years, different amyloid proteins were discovered and the mo lecular basis of the different amyloid syndromes was elucidated. The increase in knowledge parallelled the availability of modern, ingenious and also rapid methods in the biomedical sciences.