Dear Colleagues: It is the 75th anniversary of the appearance of Alonzo Church's fundamental article "An unsolvable problem of elementary number theory". This paper introduced to a general mathematical audience the (untyped) lambda calculus as a computational paradigm. This calculus has profoundly influenced not only the foundations of computer science but also a wide range of areas, including category theory (via cartesian closed categories), logic and linguistics. There will be a one-day celebratory workshop June 15, 2012 at the University of St. Andrews, Scotland, as part of the 2012 Symposium on Trends in Functional Programming. Here is the workshop webpage: http://msp.cis.strath.ac.uk/lambda2012/ Keynote speakers include: H. Barendregt (Nijmegen), C. Hankin (Imperial), F. Kamareddine (Heriot-Watt ), G. Plotkin (Edinburgh). In addition to the keynote speakers, there is a call for workshop papers on any topic relevant to the life and work of Alonzo Church. Deadline for submissions is 27 January, 2012. See the workshop webpage for further details. Philip Scott [For admin and other information see: http://www.mta.ca/~cat-dist/ ]