The 22nd ACM SIGPLAN International Conference on Functional Programming (ICFP 2017) took place in the Mathematical Institute in Oxford from 3rd to 9th September 2017, chaired by Jeremy Gibbons and colocated with Formal Structures for Computation and Deduction. ICFP provides a forum for researchers and developers to hear about the latest work on the design, implementation, principles, and uses of FP, from theory to practice and from academia to industry. The premier conference in FP, it has been running in the current form since 1996, evolving as the merger of previous conference series on Lisp and Functional Programming and Functional Programming Languages and Computer Architecture that together date back to 1980. The conference has been steadily growing in size, and set new records again this year: 444 registered participants for the main conference, and 594 for whole week of events, which also included the Haskell Symposium and Commercial Users of FP, ten smaller workshops, and ten half-day tutorials. In addition to keynotes from Chris Martens on “Compositional Creativity” and John Launchbury on “Assuring AI”, the main conference featured 44 accepted papers (the talks were livestreamed, and the proceedings appear as Volume 1, Issue 1 of the new journal Proceedings of the ACM on Programming Languages, PACMPL), and the week closed with an Evening of Algorithmic Arts at the Old Fire Station.