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.
One thing you should consider is that some breeds are more likely to be aggressive than others.
Before they were domesticated, dogs had to fight for everything from food to territory – so signs of aggression were essential to their survival.
Many of these has been bred out to create the perfect family dogs we know today, but other retain the wilder characteristics.
There can be good reason for this – for example for those used as service or guard dogs – but prospective owners should be aware that this is the case before choosing to welcome a certain dog into their homes.
It should also be said that individual dogs may display attributes that are unusual for their breed, and all dogs have the potential to be aggressive in certain situations.
That said, here are the 12 breeds that tend to be placid pets.
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1. Labrador Retriever
One of the reasons that the Labrador Retriever is the world's most popular dog is its lack of aggression. Vigorous licking of faces is the main thing to look out for with this good natured breed. | Canva/Getty Images
2. Portuguese Water Dog
Sometimes aggression can be caused due to a lack of understanding so often the most intelligent dogs can be the least aggressive. The Portuguese Water Dog is one such bright spark that has the added bonus of being low-shedding so suitable for allergy sufferers. | Canva/Getty Images
3. Golden Retriever
What's true of the Labrador Retriever is also usually true of close cousin the Golden Retriever. That's certainly true when it comes to levels of aggression. Other than enjoying a nibble of their owners when teething, this is a dog whose main emotion is love and devotion. | Canva/Getty Images
4. Japanese Chin
A more unusual breed in the UK, the Japanese Chins are known for their sweet, loving, and affectionate nature. They may well be vocal when it comes to strangers coming into their homes, but that's pretty much where any aggression will stop. | Canva/Getty Images