I would like to start by wishing all our readers a happy, healthy, and prosperous New Year.

In this issue, we have two special sections. The first is concerned with program debugging. I would like to thank the guest editors, Sudipto Ghosh and Jenny Li, for helping to bring together a set of inspirational papers on this important theme. The guest editors have provided a very helpful introduction to this special section.

The second special section concerns the synergies that exist between Artificial Intelligence and Software Engineering. I am very grateful to the guest editors, Çetin MeriÇli and Burak Turhan, for all their hard work on eliciting and editing the papers for this section.

As always, I hope you enjoy reading these papers. Please contact me if you have any comments on this issue. My email is rachel.harrison@brookes.ac.uk.