Dear colleagues and friends, I am writing to let you know that the next Peripatetic Seminar on Sheaves and Logic (PSSL), the 104th, will be held in Amsterdam during the weekend of October 6 and 7, 2018. We will use the occasion to celebrate the 60th birthdays of Jaap van Oosten and Thomas Streicher. Further details will be available in due course. In the meantime, please do not hesitate to contact me if you have any queries. With best regards, Benno van den Berg [For admin and other information see: http://www.mta.ca/~cat-dist/ ]