The importance of this question cannot be overstated. It is vital that a breeder introduce every pup to the world- many objects, sounds, people and places as well as other animals at the appropriate age. Once a litter is old enough, socialization is one of the most important responsibilities a breeder has. A good breeder will give you plenty of information on what a pup has experienced so far, and provide advice on how to continue a pup’s socialization.