Even on holiday, small business owners cannot seem to fully escape concerns about what happens at the office back home, according to new research.

The American Express Small Business Monitor indicates that 65 per cent of US owners of small companies worry about their business while on holiday.

Of this group, 39 per cent are concerned that customers will not receive the same level of service in their absence, while 26 per cent worry about staff judgment calls, the survey reveals.

"Small business owners are optimists by nature - in fact, the survey shows that 87 per cent see the glass as half full," said Alice Bredin, small business adviser at OPEN from American Express.

"But when they're not in the driver's seat, even if for a few days, they often can't relax."

When they do manage to disconnect, 35 per cent of respondents said that they have good ideas which could lead to business growth.

In related news, Mintel recently reported that Britons spent £23.8 billion on overseas holidays in 2006.