Crate training is the term commonly used to describe the process of placing dogs in a carrying device (such as an airline carrier ) or housing device for the purpose of housetraining.
The principle is quite simple. Domesticated animals still rely heavily on their instincts, despite their domestication and separation from their wild state.

Watch a show on the wild dogs of Africa and you see that they often house themselves in the ground in a space called a “den.” Instinctively the mother dog cleans up urine and stool after the pups until they are old enough to go outside. Once they reach that age and level of maturity those same instincts tell them that if they urinate or have bowel movements in the den, they have to sleep with it. Naturally, doing so is unpleasant, so they develop habits to avoid the unpleasantness.
In crate training you have simulated the den environment by placing your pet in a small area. Water should be always available and food can be delivered there at the proper feeding interval two or three times daily. After a puppy reaches sufficient maturity (the age of which varies from one individual to another) and the urge to defecate or urinate arises, the close quarters of the “crate,” simulating the den environment, will suppress the urge and prevent the soiling of his bedding.

Naturally, this urge suppression has limits, so a pet in crate training must still be taken out to use the bathroom on a regular basis. The less mature the pet, the more frequent must be the bathroom breaks.
The whole system breaks down if not tempered with common sense. If a crated puppy is allowed to defecate and/or urinate in his crate repeatedly, that becomes the norm for him, and he continues that behavior. Then we are no longer practicing crate training, but torture.
Also crucial is the need to keep everything about the crate positive. Never scold your puppy in or around the crate. Never administer medications (except tasty ones!) in or near the crate.
A crate door can also be left open during “freedom” times to allow the baby to use it as a bed or sanctuary. When you have a party, noisy visitors or small children whom your puppy might find annoying, he can escape to his carrier. When there, he needs to know he can be alone and not chased or bothered.
Everything about housetraining depends on routine. Puppies need to have each step in their lives occur at the same time every day until their compliance is near-perfect. Owners of new puppies don’t get the luxury of flexibility until housetraining is complete and the puppy is older. Maturity brings the ability to “hold it” longer, but each puppy reaches that point at his own time. Read this post to learn about the fundamentals of scheduling meals and bathroom trips.
See you Monday, Dr. Randolph.
MMCRATE
Good information. Thank you.
Thank you, Alan.