  This volume contains the revised versions of papers presented at the Fourth
International Workshop on Verification and Program Transformation (VPT 2016) on
April 2, 2016 in Eindhoven, The Netherlands. The workshop is an event of the
European Joint Conferences on Theory and Practice of Software (ETAPS 2016).
  The aim of the VPT workshops is to provide a forum where people from the area
of program transformation and the area of program verification can fruitfully
exchange ideas and gain a deeper understanding of the interactions between
those two fields. The research papers which have been recently published in
those fields, show that the interactions are very beneficial and, indeed, go
both ways. In one direction, methods and tools developed in the field of
program transformation, such as partial deduction, partial evaluation,
fold/unfold transformations, and supercompilation, have all been applied with
success for the verification of systems, and in particular, the verification of
infinite state and parameterized systems. In the other direction, methods
developed in program verification, such as model checking, abstract
interpretation, SAT and SMT solving, and automated theorem proving, have been
used to enhance program transformation techniques, thereby making these
techniques more powerful and useful in practice.
