It is estimated that up to 70% of people driving abroad are unaware of traffic regulations in any of the European countries, with many of these being company car drivers.
Concerns have been raised over the issue this week by driver training specialist and fleet management company Pro-Drive and in a new report produced by the RAC.
Pro-Drive operations director Paul Sturgeon said: 'When taking our cars abroad, most people tend to spend time checking their documentation, insurance policy and that their breakdown cover is valid for the countries they are visiting.
'It's important that this is done as without these checks you may be left stranded in the event of an accident or breakdown.
'However, documents don't protect lives and, having made these checks, most people drive off the ferry or Eurostar train, or collect a hire car, and only then think about the implications of what lies ahead of them on a foreign road.'
The company said fleet drivers using their own cars overseas were at an immediate disadvantage because of impaired visibility. In a hire car, they needed to get used to different controls, it added.
Sturgeon said: 'All we ask is that drivers spend time getting used to their vehicle and new environment before entering the road network as it only takes one moment of distraction to cause an accident.'
The RAC study said its estimate that 70% of motorists were unaware of individual country motoring laws was putting motorists abroad at risk of accidents or fines.
Mark Hodges, of RAC Legal Services, said: 'The costs of legal disputes, accidents and fines abroad can be huge so people are at real risk.'