The 39th Denver Conference on Applications of X-ray Analysis was held July 31-August 4, 1995, at the Sheraton Hotel, Colorado Springs, Colorado. The year 1995 was a special year for the X-ray analysis community, since it represented the 100th anniversary ofthe discovery ofX-rays by Wilhelm Roentgen. In commemoration of this event, the Plenary Session of the conference was entitled THE ROENTGEN COMMEMORATIVE SESSION:1895-1995, 100 YEARS OF PROGRESS IN X-RA Y SCIENCE AND APPLICATIONS . It is interesting to note that while we celebrate 100 years ofthe use ofX-ray techniques in general, and about 80 years ofX-ray diffraction and spectroscopy in particular, the Denver X-ray Conference has been in place for about half ofthat time period! Like the X-ray methods it represents, the Denver Conference on Applications ofX-ray Analysis has grown and matured, has survived the rigors oftime, and today, provides the worlds’ best annual forum for the exchange of experiences and developments in the various fields ofX-ray analysis. Imagine, when the Denver Conference started in 1951, there were no personal computer- in fact, there were no computers, period! There was no SEM, no microprobe, there were no Si(Li) detectors, no transistors, no synchrotrons, Hugo Rietveld was a child, and many members who regularly attend Denver Meetings today, weren’t even born yet! As I write this foreword, a copy of volurne 1 of Advances in X-ray Analysis lays in front of me on my desk.