Financial services firms in the U.K. must prepare now for new reporting rules aimed at promoting operational resilience in the face of increasing global threats. Key issues for compliance include understanding what issues will cross the threshold for reporting obligations, how incidents are defined, and how they should be reported.

Ruth Prickett graduated from Cambridge University with a BA hons in History and has specialized in business and finance journalism for the past 20 years. She was editor of Financial Management, the magazine...