Personality
Cairn Terriers are intelligent, lively, strong, and loyal. Like most Terriers they are stubborn and strong-willed.
Cairns are working dogs and are still used as such in parts of Scotland. Many Cairn Terriers are very independent and do not make good "lap dogs". The image of Cairn Terriers as Toto from the Wizard of Oz is a partial misconception. In reality these dogs do not always like to sit in laps and snuggle, and they would heartily object to being kept in a basket.
Trainability
Cairn Terriers have a strong prey instinct and will need comprehensive training. However, they are highly intelligent and, although very willful, can be trained. While it is often said that they are disobedient, this is not the case provided correct training is applied. They are headstrong and should always be walked with a leash.