Families of substantial wealth now consider succession planning to be their biggest concern, overtaking capital preservation as the main challenge in the last three years.

This is one of the findings from multi-family office Stonehage Fleming’s Four Pillars of Capital: Practical Wisdom and Leadership for Changing Times report, which surveyed 150 people from "ultra high net worth" families, and their advisers.

Succession planning was a “top three” concern for 69 percent of families, compared to the 59 percent who cited it in the same study in 2015. Capital preservation was cited by 62 per...