PERIPATETIC SEMINAR ON SHEAVES AND LOGIC 70th meeting -- First Announcement The 70th meeting of the PSSL will be held in Cambridge on the weekend of 27-28 February 1999. As usual, we welcome contributed talks on any aspect of category theory, sheaf theory or related areas of logic and computer science. It is planned to make this meeting into a celebration of the 60th birthday of Gavin Wraith, which falls in March 1999. Gavin has been involved with the PSSL since its inception in 1976, and we hope that his many friends will wish to join us in celebrating this occasion. Further details of the arrangements for the meeting, and a registration form, will be sent out in January. Peter Johnstone Martin Hyland Chris Mulvey