What Are They and What Is the Difference?
There are many ways to acquire a new dog and some methods are definitely better than others.
Puppy mills, pet stores, shelters and dog breeders are the most common sources of new pets for most people.
Carefully examine the nature of each of these venues before buying a dog.

Puppy Mills
The term "puppy mill" refers to any breeding facility that breeds dog for profit only.
Very little attention is paid to the animals and breed standards are not held to.
In the worst of the puppy mills, dogs are stacked up in cages, are underfed and given very little medical care.
The dogs are continually bred, heat cycle after heat cycle, giving the female dog little or no time to recover before she is impregnated once again.
The conditions under which these dogs are kept and bred often produce dogs with minor to major behavioral and medical problems.
Not all puppy mills are large facilities.
Even the "backyard breeder" who breeds dogs only for profit and not for the benefit of the breed is considered by many to be a puppy mill.
The prices you'll pay to a puppy mill may be less than what you would have paid for a dog from a reputable breeder,
but you may end up paying more in the long run anyway.
Dogs from puppy mills are usually plagued with medical problems (resulting from a lack of proper medical care and malnutrition)
that require an excessive amount of medical exams, shots and medication.

Pet Stores
No trip to the mall would be complete without a walk through the pet store, right?
All of those cute little puppies, so excited to see you!
It's a miracle that anyone ever makes it out of a pet store without taking one of those cuties home with them.
The animals from a pet store might appear to be well cared for and the store's staff
may vouch for the health and quality of their inventory, but the truth is usually something entirely different.
The only source of dogs for today's pet store is the puppy mill.
No reputable breeder would allow his or her dog to be displayed and sold in such a manner,
so what other kind of breeder is left?

Shelters
If you don't really care about the breed of a dog and are simply looking for a companion animal,
your local animal shelter is a great place to begin your search.
Dogs of all ages and sizes are available.
Many shelters allow you to play with a dog and spend some time
with it before you make the final decision as to whether or not you want to adopt it – they want to make sure the fit is just right! For an adoption fee, you'll get a new dog that has been fixed, vaccinated and injected with a microchip.

Breeders
Reputable breeders are the best option if you're looking for a purebred puppy.
A reputable breeder is one who works for the benefit of the breed, not for profit and who cares where his or her puppies end up.
Expect to be questioned about your plans for the dog and don't be surprised if, after a conversation or two, the breeder decides that your home would not be the best one for their dog.
If you are approved by the breeder, you will probably have to sign some sort of contract in which you agree to:
immediately spay or neuter a dog bought for companion purposes only;
notify the breeder of any medical conditions that the dog develops;
notify the breeder if you have to get rid of the dog so that he or she can find it a new home;
and, breed your dog (if that's why you're buying it) in accordance with breed standards.
The actual contract might include other stipulations as well.
This may seem a bit stringent, but the breeder is only trying to ensure the health and well-being of the animal.
A pet you buy from a responsible, reputable breeder can be very expensive, but you'll know that your new addition to the family is as healthy as he can be and free of genetic defects.
Where do you find a reputable breeder?
Once you decide on the breed that's right for you, check with the relevant local and national breed clubs.
They will be able to recommend a breeder in your area.