Dear colleagues and friends, This is the second announcement for the 104th Peripatetic Seminar on Sheaves and Logic, to be held in Amsterdam on the weekend of October 6 and 7. We will use the occasion to celebrate the 60th birthdays of Jaap van Oosten and Thomas Streicher. For more information we refer to the website: http://mysite.science.uottawa.ca/phofstra/PSSL18.html In particular, we encourage people who wish to attend to arrange their accommodation as quickly as possible, because Amsterdam is a popular destination. The organizers Benno van den Berg Pieter Hofstra [For admin and other information see: http://www.mta.ca/~cat-dist/ ]