REACH A CERTAIN prominence in public life and you may be invited to become a non-executive director. The most lucrative option is to join the board of a large company. But for social prestige, there is nothing quite like joining the board of a cultural organisation. In Britain, these boards are dominated by “the great and the good”—aristocrats and wealthy businesspeople.

Sir John Tusa, a former BBC executive, has written a guide based on his extensive experience among Britain’s literati and glitterati. “On Board: The Insider’s Guide to Surviving Life in the Boardroom” is a useful primer for any board member. The job, Sir John argues, is not all about free tickets and lavish dinners. “There is no difference between governance on a corporate board and an arts board,” he says. “Sitting on a board, let alone chairing one, is one of the most demanding, complex and taxing activities in the world of public life.”

The book also gives an inside glimpse of the political battles that were fought over the future of venerable institutions such as the British Museum, English National Opera and the National Portrait Gallery. Cultural boards face a constant tension between the need to get funding from the government and the artistic ambitions of their executives, a dilemma made even thornier by the need to repair crumbling or outdated buildings.

Such was the traditional nature of these institutions in the years when Sir John operated that the book is sometimes redolent of the interwar era. He was invited to join the board of the British Museum over lunch at the Garrick, a gentleman’s club founded in 1831. He then discovered that board meetings were held on Saturday mornings because a former Archbishop of Canterbury, when a trustee, had requested the time slot as it allowed him time to write his Sunday sermon in the afternoon.

Perhaps this old-fashioned atmosphere (which has now been changed by bringing in a wider range of trustees) led to some of the difficulties that Sir John describes. Too many appointments were rushed, he says, forgetting the first rule: “If you can’t see the right candidate in front of you, don’t appoint.” One frequent problem he faced was tension between the chairman and chief executive, so he suggested that one-to-one discussions between the two should be part of the appointment process to ensure compatibility. When in their posts, the duo should aim to talk every day.

Even then, the chairman (or woman) must retain a certain air of detachment. The boss’s approach, says the author, can be summed up by the quote: “We are totally on the same side until the day that I have to sack him.” Bad chairmen tend to impose their views, fail to respond to ideas and refuse to alter their approach. Often they place their favourites on the board, creating factions and causing destruction.

Sir John’s advice to chief executives is to tell the board what they are doing, when, how and why—all in order to persuade board members that the boss deserves support. But CEOs should not deluge trustees or directors with paperwork: “If information is power, it must be remembered that too much information is a smokescreen.”

As for board members, Sir John says they should ask questions of the executive, and be careful about accepting the answers too easily. They should also remember that there is no such thing as a stupid question. And it is not their job to develop strategy: “The executive proposes, but the board disposes,” he says.

Trustees should be chosen with a view that one of them is capable of chairing the board in due course. Furthermore, trustees should know why they have been invited to join the board and how they might best contribute to the organisation’s success.

All Sir John’s suggestions seem sensible and most would apply to public companies as well as to arts institutions. The role of non-executive directors has never been well defined. Tiny Rowland, a swashbuckling tycoon, dismissed them as “Christmas tree decorations”—just for show, in other words. Think of the great names that studded the board of Theranos, a blood-test startup, and how they failed to stop its collapse.

Most non-executives do their best but are caught between two stools. They do not know enough to challenge the executives properly. But if they push their questions too far, they will not be reappointed. Above all, trustees and non-executive directors cannot do their job unless the management wants their input. Wise bosses should know their limitations and rely on boards for advice.

This article appeared in the Business section of the print edition under the headline “How to play the board game”