In May 2010, the coalition government made a commitment to trial the use of Payment by Results (PbR) for children's centre services to incentivise a local focus on the core purpose of children's centres. The Department for Education (DfE) began the trial in September 2011 and it lasted 18 months until March 2013. The trial involved 26 trial areas covering 27 Local Authorities (LAs) with one area consisting of a joint trial for two LAs. This report presents the findings from a process evaluation of the trial considering whether and how the tested PbR scheme achieved its objectives. (author abstract)