Yes, they wee on the floor, demand long walks in the rain and have a tendency to chew your favourite shoes.
But you don't have to change their nappies, wipe their bottoms or pay out a fortune for babysitters - so it's not difficult to see why four in ten adults think that having a dog is a good alternative to having a baby.
According to a new survey by The Kennel Club, 40 per cent of couples think that a four-legged friend makes a good baby substitute - and 25 per cent of parents say that, although their children come first, they actually prefer going out with their dog!
This is mainly because of the unconditional love and devotion that dogs show to their owners, as 80 per cent of dog owners praised their pet for being loving, while just 50 per cent said the same about their partner.
Also, dogs are unlikely to throw a tantrum if you won't buy them a new toy and tend to eat anything that's put in front of them.
Then again, maybe we just use a new puppy as a trial run for having kids? After all, once you've adjusted to the responsibility of caring for - and cleaning up after - a dog, the prospect of taking care of a baby might not feel quite so daunting...