I am honored that it is my privilege to present to you this two-day symposium on the analysis of high-boiling petroleum oils, which has been prepared by Research Division IV of ASTM Committee D-2 on Petroleum Products and Lubricants under the sponsorship of the Division of Refining of the American Petroleum Inst. In the opinion of the Planning Committee, this symposium represents the first time that such a broad coverage by such an acknowledged group of authorities has been presented on this important subject. The interest in this topic is indicated by your attendance in such great numbers. Your presence lends prestige to this important undertaking and, might I say, cancels many of the apprehensive moments that I have had during the year and a half that it has taken to develop this program. Certainly, your presence and interest will be most gratifying to the men who have prepared the papers which are to be presented. Such an undertaking as this could not occur without the willingness of these men of knowledge and the cooperation of the organizations with which they are connected. It was the original thought of the committee that we should obtain the most authoritative information available on the subject of hydrocarbon types analysis of heavy oils. The authors of papers covering the many phases of analysis are the experts in their respective fields. The willingness of these scientists to expend their time and effort that we might gain from their knowledge is of great inspiration. Our appreciation is due them for their most important part and cooperation in making this meeting most meaningful to all of us.