Efforts to improve female representation on U.K. boards has improved in recent years, but it is mainly non-executive roles where change has been more immediately made. For example, according to the New Financial report, Women in U.K. Financial Services 2016, women CEOs in the U.K. financial services sector still only account for 6 percent of the total—the remainder are dominated by the “male, pale, and stale” brigade.

Consequently, on Aug. 12, the Prudential Regulation Authority (PRA), the Bank of England’s body in charge of supervising regulation in U.K. financial firms, published an open letter—as a “gentle reminder”—of the important role that diversity plays in promoting good governance. It was also intended to nudge firms to remember the mandatory obligations they need to take to improve gender diversity in the boardroom.

Neil Hodge is a freelance business journalist and photographer based in Nottingham, United Kingdom. He writes on insurance and risk management, corporate governance, internal audit, compliance, and legal...