Mij, who has saved more lives than any other dog, has retired after a seven-year career that has seen her save 14 lives.
The Collie, who has led more than 200 search and rescue missions, pioneered scent detection techniques which have since been used in some of the country's most high-profile missing person searches.
During her career she became known as the most dependable dog and was called upon by police and search teams across the country, helping to save people from Scotland to Cornwall.
One of her greatest moments came during the search for an elderly woman who had been missing from her home for more than 24 hours.
Despite a 100-strong team's best efforts, there was no trace of her and Mij was called in.After sniffing an item of her clothing Mij traced her final steps and within minutes had located the woman and helped to save her life after she had fallen into wild bushes that completely surrounded her from eyesight.
Owner Iain Nicholson, from Preston, Lancashire, said: "It was truly one of her greatest moments and helped her to become known up and down the country. The woman Mij saved would never have been found but thanks to her she was rushed to hospital and made a full recovery.
"Mij is courageous and her technique allows her to pinpoint the exact person's scent even if she were surrounded by hundreds of others.
"Police used to ring me up and ask if Mij could come and help search for someone in the Lake District, Cornwall, Scotland and so on - we've been all over the country in her time."
The ten-year-old Collie suffered health problems as a puppy that hindered her stamina as a youngster, meaning she was unable to follow traditional training techniques for open area search dogs.
Her trainer and owner Iain refused to put her down and with expert Tom Middlemas, taught her to conquer the art of scent discrimination so she can now distinguish an individual from a crowd of thousands with clinical accuracy.
The method revolutionised the way rescue dogs search in the countryside and is now considered to be at the forefront of training throughout the world.
Paul Durham, of the National Search and Rescue Dog Association, said: "Mij was the first in the UK England to master the method and is now helping to train the new generation of 20 dogs.
"She attended the most search and rescue missions for a trailing dog and the number of people she saved was considerably higher than any other - she is truly remarkable.
"Mij could not be trained as an open area dog as she suffered from poor stamina as a puppy and wasn't able to run around a large areas to search - she changed disciplines and honed her skills in narrow scent discrimination trailing search work.
"Rather than prevent her from being a normal search dog Iain saw so much potential in her that handlers need and helped her become the best rescue dog in the country."
Iain, who is the one of the UK's leading rescue dog trainers, now uses Mij’s success to train other rescue dogs.
Harold Burrows, Chairman of NSRDA, said: "While bloodhounds traditionally used a tracking method to follow footsteps and lead search teams down a certain path, Mij identified the unique scents humans leave behind as they walk.
"The process is incredibly valuable and completely transformed the searching process - rather than organising a team to search in a 360 degrees area Mij can tell us exactly which way a missing person went saving crucial hours.
"It can make the difference in a life or death situation."