Many times when I am contacted by potential puppy buyers, one of the first things they say is that they were scammed by a breeder, or they had contact with breeders who they considered to be running puppy mills. We honest breeders are disturbed by this, as it gives breeders in general a bad name. I would consider a reputable breeder to be one who is open and transparent with buyers. A reputable breeder should know all about the breeds they sell. A good breeder will probably only breed one or two breeds, and be well versed in the issues of that breed. Genetic health testing is easy to do these days, and gives good information to breeders on which dogs can safely breed without producing puppies with possible genetic defects. A reputable breeder should be willing to run genetic health test on any puppy who is being purchased as breeding stock. I find it quite frustrating myself when I am looking to buy a puppy and the breeder either does not test, or is not willing test a puppy. A reputable breeder should concentrate on health first and foremost, and with socializaton, of both puppies and the adult dogs. Puppies should be raised inside, and socialized with people, and with other dogs. They should be started on potty training. Cleanliness should be a big focus, and parasite testing should be done in addition to regular worming, and age appropriate vaccinations. Adult dogs should be kept in as home like an environment as possible. My own dogs live either in the house, or in temperature controlled buildings with open fenced yards for them to play in. We do not have kennel runs or concrete runs. All adults spend regular time in the house. It is important that breeding dogs, and puppies, are given high quality diets, and regular vet care. Be sure to ask about diet and the vet care regime. Most good breeders will be willing to provide references from past buyers. They often have repeat buyers, and do a fair amount of their business based on referrals. They often have waiting lists for puppies. They should also be willing to provide vet references if asked. The buyer should received updated pictures of the puppies on a regular basis. You should be welcome to visit the breeder’s facility, and see both the puppies and the adults. If you are buying long distance, check out local references, or references from past buyers. ” Be cautious of any breeder who only wants to communicate by text, who wants full payment up front, and who says they will deliver with their personal pet porter. This is a big red flag. Although there are a multitude of definitions of a puppy mill, basically a puppy mill is a breeding operation that puts profit over health and well being of dogs and puppies. Dogs are not given quality food, vet care, and not socialized on a regular basis. Do your homework, and you should end up with a happy, healthy puppy.