The 43rd Annual Conference on Applications ofX-ray Analysis was held August 1-5, 1994, at the Sheraton Steamboat Resort & Conference Center in Steamboat Springs, Colorado. The Denver X-Ray Conference has evolved from the 1950's into an international forum for the interaction of scientists, engineers and technologists interested in the use of x-rays in materials characterization. It has not only acted as a venue but has both stimulated and nurtured many of the principal developments in this field over the years. The major changes that have been occurring on the national and international scene as a result of the end of the cold war have dramatic-ally affected the way the materials community does business. The removal of defense priorities and development funds from most new materials initiatives has stimulated the char acterization communities to look to increasing the speed of their methods. This is being accom plished via the development of very fast dynamic characterization procedures which can rapidly and intelligently monitor and optimize the formation of a desired microstructure. The develop ment of intelligent characterization procedures applied in real-time during the manufacturing process can lead to the ability to design desired microstructures. Another potential advantage to this approach is its ability to characterize the actual amount of material which goes into a final product; permitting a rapid transition from R&D to manufacturing by avoiding the prob lems associated with scale-up.

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.

89 articles organized under the following section heads: Impact of Computers on Xray Analysis. Applications of Whole Pattern Fitting: Structure Determination, Phase Identification, Lattice Parameters. Search/Match Methods, Phase Identification. Diffraction from Single Crystals and Epitaxial Films. Xray Characterization of Films and Surface Layers. Strain and Stress Determination, Xray Fractography, Diffraction Peak Broadening Analysis. Advances in Detectors and Counting Electronics. XRD Techniques and Instrumentation, Nonambient Applications, Texture, other Applications. Xray Optics, Monochromators and Synthetic Multilayers. Total Reflection XRF Applications and Instrumentation, other XRF Techniques and Instrumentation. Mathematical Techniques in Xray Spectrometry. Geological and other Applications of XRS. Index.

The 41st Annual Conference on Applications of X-Ray Analysis was held August 2-6, 1993, at the Sheraton Denver Technical Center Hotel, Denver, Colorado. From its modest beginnings in the early 1950's, the Denver X-Ray Conference has grown to become a major venue in the national scientific calendar, with an ever-growing overseas participation. The 1993 Conference was the latest of these annual gatherings of x-ray analysts, who come together to discuss topics of current interest in diffraction and fluorescence. As the size and flavor of the Conference has changed over the years, so too have the methods and techniques of x-ray materials analysis matured. Science is advanced by the creativity of a few and the mistakes of many. It is important, therefore, that from time to time we sit back and reflect on how we got where we are, and where we are likely to go next. There has been no greater impact on the field than the introduction of the digital computer, and the Plenary Session of the 1993 Conference, "Impact of the PC in X-Ray Analysis," was designed to reflect on the role of the personal computer in the metamorphosis of x-ray instrumentation and techniques. Since the personal computer is a creation of non-x-ray specialists, we, as a group, have simply attached ourselves to the coat-tails of experts and developers in the PC field and taken advantage of new computer systems as and when they were developed.