Want to know which small breed dogs are popular in North America? Let’s discover the 15 cutest dog breeds. West Highland White Terrier: The West Highland White Terrier is a small breed dog who has a face to die for. Not only are they happy and cuddly, but they also make great watchdogs because they will be sure to alert you when they hear noises. Having an alert dog is great. However, it’s important to train them early because Westies are known to be excessive barkers, so if you don’t want your ears full, start the training process now.