Prof. G. Pezzin(University of Bologna, Italy). Dr. Wales will start by discussing his own results and perhaps other results on slip of PVC. Professor Lyngaae-Jorgensen will expand a little on fusion. Dr. Chauffoureaux will discuss a new topic which will be interesting for most of the technologists present who have problems with PVC processing; in particular, the problem of the measurement of friction at high temperatures. Dr. De Vries, Dr. Collins and myself can perhaps add something by answering questions.