Polyolefin is one of the most important materials produced in the chemical industry. The research in this area is not only scientifically challenging but also potentially economically rewarding. Many research activities, such as developing new catalysts, understanding polymerization mechanisms, modifying the products and improving the physical properties of the material, have been proceeding at a very fast pace, especially in the industrial laboratories in many countries. It is very important and exciting to bring researchers active in this area, from both the academic and industrial sectors, to communicate their new findings. To the best of my knowledge, a symposium covering diverse aspects of polyolefin research has not been held in the USA for many years. With this in mind, a symposium entitled "Recent Advances in Polyolefins" was held at the National ACS Meeting in Washington D. C. , August 23-28, 1992. This symposium covered both scientific and technological aspects of polyolefin, which included four sections: CatalystIPolymerization, Functionalization of Polyolefins, Blends of Polyolefins with Other Polymers, and Applications. More than 50 papers, including 20 foreign contributions, were presented during three and a half days of meetings. It was truly exciting to see key researchers from both academic and industrial laboratories exchange their recent results and to share the important developments in polyolefins. This volume is based on the same spirit and is intended to capture some of the most recent and emerging technical achievements presented at the meeting.