The Symposium XVI for the Study of Underdrawing and Technology in Painting. The Quest for the Original, Bruges-September 2006, was organized by the Laboratoire d'etude des uvres d'art of the Universite catholique de Louvain, in collaboration with Illuminare, Centre for the Study of Illuminated Manuscripts of the KU Leuven and KIKIRPA, Royal Institute for Cultural Heritage, Brussels. Articles are on painting of the Low Countries, Italy, France, Germany, Denmark... between medieval and modern times, not only easel painting, but also book illumination, painting on glass and ceramics and framing in the Southern Netherlands (15th until 17th c.). Some methodological issues are discussed. Molly Faries accepted to share her experience for an update on equipments for examination of paintings in the Infrared. The organizers had received for presentation in Bruges more interesting papers than they could accept; they include some of them in this publication. The volume also presents a bibliography in the infrared studies for the years 2005-2007.