The group organises the 4th International Workshop on Processes and Data at Gregynog. The conference was highly successful and fun. The talks and discussions held were based around "The Formal Semantics of Programming Languages" book by Glynn Winskel. Markus firstly introduced Operational Semantics, before Liam gave a small proof around the operational semantics. Finally Phil spoke on Denotational Semantics. To bring the conference to a close, Temesghen spoke on some of his current results from his PhD Work. Below are some photos from the trip.