A national Scottish police force would be better equipped to deal with major incidents such as the Derrick Bird shootings, a top officer has said.
Strathclyde Police Chief Constable Stephen House said smaller individual forces could not respond alone to large-scale emergencies.
Mr House made the comments ahead of a conference on the future of policing.
The Scottish government has begun a consultation on how to reform the police and fire service.
Mr House is due to outline his support for the plan to amalgamate all Scotland's police forces at the Policing Scotland Summit in Edinburgh on Tuesday.
In advance of the conference, he said: "The tragic experiences of the Derrick Bird shootings in Cumbria last year were a huge drain on resources.
"That small force - and I say small, but they are certainly larger than some of the current forces in Scotland - needed assistance from many other forces.
"Now there is nothing wrong with that as a model per se, but how much more robust would a single police force for Scotland be in its response to a major incident and to the need for specialist policing?
"We would not need a series of ad hoc mutual aid agreements. If a major incident happened, we would not need a series of hurried phone calls between forces regarding resources.
"We would be able to act as one organisation to make sure that what was needed was done."
Other speakers expected to attend the conference include Justice Secretary Kenny MacAskill and Northern Constabulary Chief Constable Ian Latimer.
Mr House said the current eight forces followed the template of regional government from the 1970s.
He said: "I doubt that anyone can argue against the often quoted notion that if we were sitting with a blank sheet of paper deciding how to police Scotland, we wouldn't come up with a model that has eight forces supported by national agencies.
"It doesn't make financial sense, nor does it make operational sense."
He said the benefits of merging the forces would be felt across Scottish communities.
There has been concern that any move to amalgamate the forces could result in a loss of local knowledge, but he said local commanders would make plans for their own area.
Mr House said: "It would be folly to think that someone in the centre could or indeed should have sufficient local knowledge to deliver the right type of policing in all areas of the country."
He added: "An argument strongly and emotionally advanced by those who are against a single force is this idea that as soon as it is created you will see a drain on resources from across the country into the central belt."
But using such arguments was "scaremongering", he said.