Bailey's personality as a puppy was what the breeder called "reserved". When we saw him at the breeders, we were deciding between him and his sister. His sister came charging up the stairs when let out and jumped all over us and ran around the room--kinda normal confident puppy behaviour. Bailey on the other hand, went around exploring the room calmly, but slinked away from us when we tried to pet him and shook when we held him. He was our first dog and looking back now, we should have been worried about his behaviour/tempermant/socialization. But we got him and we socialized him like crazy. During those first weeks, we diligently went through long list of things/peoples/situations to socialize him to and enrolled him in puppy class and doggy daycare and his confidence skyrocketed. Still in terms of nature versus nuture, Bailey continues to be the type of the dog that is cautious and will bark and be fearful of things he finds slightly odd/different (e.g., people being piggy-backed, kids in puffy snowsuits). He is a lovely, sweet, and calm boy aroudn the house (although not a big cuddler) and energetic and fun when out.