Wealthy Americans believe a strong work ethic is behind their wealth, but their families will have to be innovative to sustain it – and may need to reinvent the family business.

That’s according to a poll by investment manager SEI, which found that 80% of high net worth individuals in the US said their work ethic was either important or the most important quality behind achieving their wealth.

But sustaining such affluence could prove difficult – 95% said innovation would be important to their families' ability to continue being successful.

“The results point to the realisation among wealthy families that sustaining wealth for multiple generations requires an ability to adapt to changing conditions and, at times, reinvent business orfinancial strategies,” said the company in a statement.

The survey, which questioned 100 individuals representing families with more than $20 million (€15.15 million) in financial assets on average, also found there was no consensus on where this innovation should or would come from.

Almost half said professional advisers, while 37% expected innovation to come from those in business.

“After everything that's gone on in recent years, they understand that sometimes it takes a different approach to be successful," said Michael Farrell, managing director for SEI Private Wealth Management, in the statement.