Police in the Western Isles are urging drivers to be aware of vulnerable road users, particularly horses.
Officers in the islands have recently received concerned from local riders about cars passing their animals too close to too fast.
Horses and their riders are considered to be vulnerable road users - as are cyclists and pedestrians - and that should be taken into account if passing them.
Western Isles area commander Chief Inspector Ian Graham said: "Horse riders have every right to be on the road and should be able to travel safely.
"I would encourage drivers to slow down to a maximum of 15 mph and leave at least a cars' width between their vehicle and the horse if possible.
"Even the most well trained horse can be unpredictable if frightened by a car and that can put the rider, animal and even the driver in danger.
"Anyone who is found not to have given sufficient space is putting themselves at risk of being charged with careless or even dangerous driving.
"I would also encourage horse riders to make sure they can be seen as clearly as possible by wearing high-visibility clothing and giving suitable signals.
"We are planning to carry out proactive work on the roads in relation to safe driving around horses in the coming weeks and will continue working with partners to ensure the Western Isles is safe for all road users."
Alan Hiscox, The British Horse Society's Director of Safety, said: "Incidents between horses and vehicles are increasing, and this initiative to increase awareness of riders as vulnerable road users can potentially save the lives of riders, horses and drivers.
"We encourage all road users to show each other patience and courtesy, and we would also urge riders to thank all drivers who pass them safely."