Dogs come in all shapes and sizes - the UK Kennel Club recognises 221 different pedigree dogs, from Affenpinscher to Yorkshire Terrier (there are sadly no dog breeds starting with the letter ‘z’!).
Then there are all manner of crossbreeds, from so-called ‘designer dogs’ to lovable mongrels.
Each has its own list of positive and negative attributes, and it’s important to take plenty of time to think about what breed will fit into your lifestyle the best - for instance a smaller dog if you live in a flat, or a hypoallergenic dog if the mere mention of dog hair makes you think about sneezing.
There is even scientific research to guide you, in particular psychologist Stanley Coren’s groundbreaking book The Intelligence of Dogs.
It’s also worth noting that some breeds of dog tend to be naturally cheerier than others - you’d never accuse a Basset Hound of being brimming with joie de vivre.
So, if you’re looking for a dog that has a naturally sunny outlook and a mischievous smile, here are 12 that fit the bill.
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5. Bedlington Terrier
Several Bedlington Terriers have become 'Insta-famous' on social media due to their incredibly smiley faces. They may have been bred to hunt rats, but those Hollywood smiles are now more likely to catch the attention of cameras. | Canva/Getty Images
6. Pomeranian
The foxy face of the Pomeranian Spitz is perfectly designed to deliver a winning smile. It's infectious too - pretty much guaranteed to get you grinning too. Look at that wee smile! | Gareth Cattermole/Getty Images
7. Labrador Retriever
When it comes to big silly infectious smiles, it's hard to beat those plastered across the face of a typical Labrador Retriever. They have been the UK's (and the world's) most popular dog for decades and their sunny disposition is one of the reasons why. | AFP via Getty Images
8. Brussels Griffon
Another small dog breed overflowing with joie de vivre is the cheeky Brussels Griffon. Sometimes their cheeriness can grow into slight self-importance, but these wee pooches could never be described as glum or introverted. | Getty Images