I have learned that many training programs were missing out on utilizing the most critical period in a puppy's development which enables them to develop to their greatest genetic potential of a sound and stable adult. This period occurs before the puppies have received all their vaccines and owners generally don't take their puppies off their property until after all their vaccines are completed. This why trainers tend to miss this learning window that is usually almost closed by the time they see them. This is why I created, "Ozz's Puppy Playland," to provide that safe, enriched environment that puppies so badly need. Please go to "Early Puppy Exposure" for articles supporting this.