  This volume constitutes the pre-proceedings of the 27th International
Symposium on Logic-Based Program Synthesis and Transformation (LOPSTR 2016),
held on 10-12th October 2017 in Namur, Belgium, and co-located with the 19th
International Symposium on Principles and Practice of Declarative Programming
(PPDP 2017). After discussion at the symposium papers will go through a second
round of refereeing and selection for the formal proceedings.
