This volume contains the papers presented at ICFP 2009, the 14th ACM SIGPLAN International Conference on Functional Programming, held August 31-September 2, 2009 in Edinburgh, Scotland.

ICFP provides a forum for researchers and practitioners to hear about the latest developments in the art and science of functional programming. The 2009 call for papers solicited submissions on topics including language design, implementation, software-development techniques, foundations, transformation and analysis, applications, and domain-specific languages, as well as functional pearls and short experience reports. ICFP welcomes work on all languages that encourage functional programming, including both purely applicative and imperative languages, as well as languages with objects or concurrency.

In response to the call for papers, the program committee received 101 submissions: 85 regular papers (including 8 pearls) and 16 experience reports. From these, the programcommittee selected 26 regular papers and 6 experience reports for presentation at the conference.

Regular papers were evaluated according to their relevance, correctness, significance, originality, and clarity. Pearls were evaluated similarly, except that they were not required to report original research, but were expected to be concise, instructive, and entertaining. Regular papers and pearl submissions were strictly limited to twelve pages.

Experience reports were evaluated separately from regular papers. An experience report is not expected to add to the body of knowledge of the functional-programming community. Rather, it should extend the body of published, refereed, citable evidence that functional programming really works--or describe what obstacles prevent it from working. Each experience report is labeled as such in its title, and an experience report is shorter than a full paper: submissions were restricted to four pages, and final versions to six pages. Each of the submissions was assigned to at least three members of the program committee. Committee members were allowed to find external reviewers for their assigned submissions, but they were required in all cases to read the papers themselves and to form their own opinions.

Initial reviews were made available to authors, who had a two-day period in which to respond. Further online discussion by the program committee followed. Final decisions were made at a two-day committee meeting held in Portland, Oregon and attended in person by all but one committee member, who participated by telephone.

Reviewers disqualified themselves from reviewing any papers for which they had a conflict of interest, according to a set of strict criteria. Program committee members with a conflict of interest for a paper were prevented from seeing any reviews or online discussion for that paper and were required to leave the room during its live discussion.

There were three submissions by members of the program committee, one of which was accepted. These submissions were discussed after all other papers and were held to a higher standard than the other papers.