Every year, Tom Kalaris, chief executive of Barclays Wealth, urges his senior advisers to go out and read more books. So passionate does he feel about the benefits of reading that Barclays Wealth sponsors the UK’s annual Hay-on-Wye book festival, an event Kalaris attended last week.

The books he is currently reading may not feature on many people's lists for the beach this summer, but they speak volumes about his interests and what he aims to do with the division he runs.