If you want to feel like you've made a real difference as a dog owner, adopt a dog from a shelter or rescue group. There are few other ways to make such a huge difference in another creature's life.

The Humane Society of the United States (HSUS) estimates that six to eight million dogs and cats are surrendered to shelters each year. Of those animals, about half are adopted, and half are euthanized. There are simply more dogs than there are good homes for them (one reason why spaying and neutering is so important).

Some people steer clear of shelters or rescues because they believe the dogs there aren't good dogs. Nothing could be further from the truth.

• While many dogs are surrendered for behavior problems, the vast majority of those problems could have been prevented, and can be treated, with training, attention, and exercise.
• Many dogs are surrendered because of a family's change in circumstances--a move, financial loss, illness, blending of families--and not because of the dog.
• Some people don't realize how much time and work puppies, and even adult dogs, require and become fed up with the responsibility.

You can find a good fit for your home by carefully evaluating a shelter dog or puppy and introducing him to every person who lives with you.

Shelters

Shelters house animals available for adoption as well as strays. Usually they're at least partially funded by the city, but some are completely dependent on private donations.

The quality of shelters varies dramatically, depending on where it's located. Some shelters provide basic medical care, training, and spay/neutering. Others are more like holding pens than shelters and don't bother with the kind of care experts believe is essential to a dog's well-being, like a daily walk.

• The population of available dogs usually changes quickly and regularly.
• At the best shelters, the staff takes notes, and sometimes posts them, on how the dog is doing. Some shelters do extensive tests to gauge a dog's personality and what sort of home would be the best fit. Many more shelters do not, and you're on your own. (See choosing a shelter dog or puppy.)
• Some shelters allow people to put a hold on dogs they want to adopt. Before you lose your heart to a dog, make sure someone else doesn't already have a claim on him.
• Some shelters euthanize animals when overcrowded. No-kill shelters will only accept dogs believed to be adoptable, i.e., those who don't have aggression or health problems, and tend to be younger.
• If you're interested in a dog, make sure you ask how much longer he has at the shelter. That is, do you have a long time to make your decision, or is euthanasia scheduled in two days?

Rescue groups

Rescue groups are organizations that take dogs out of shelters and keep them in foster homes, and sometimes private kennels, until homes can be found. Some are breed-specific, while others take all types of dogs. Overall, they tend to give the dogs more medical and behavioral care than many shelters.

• Dogs are happier in foster homes than in shelters so it's easier to assess his personality.
• You can get a good idea of the dog's temperament and habits from the foster family, since they live with him.
• The dog is not likely to be euthanized, unless he displays a serious aggression or health issue.
• These groups often have adoption events at public places such as pet supply stores, so you can drop by and meet several dogs. If you're interested in a specific dog you've seen on the group's website, you can ask for that dog to be brought to the event.

What to think about before you adopt

Shelters can be heartbreaking places to visit--crowded, chaotic, and full of sad, adorable faces. The more prepared you are emotionally for what you'll see at the shelter, the less likely you are to lose your heart to a dog you feel sorry for rather than to a dog who's a good match for you.

Before you go to the shelter, have an idea of what you want to do with this dog--jog, play with children, take long walks, visit nursing homes, compete in organized sports, or hang out on the couch. When you're looking at dogs, remember those traits and keep your head about you. You're protecting the dog you'll eventually adopt, as well as your own heart.

If you find shelters too disturbing to visit, go to an adoption event instead. They're often held at pet stores or farmer's markets, and since they feel like field trips for the dogs, they're generally less depressing.

What to know about services and fees

No federal agency oversees shelters or rescue groups. Some people assume that the HSUS takes care of these things, but it's a nonprofit animal protection agency and has no legal authority. This means that shelters vary significantly in their levels of quality, animal care, and medical services.

A responsible and well-funded organization, whether it's a shelter or rescue group, will make sure the dog is spayed or neutered, current with vaccinations, and has been treated for any necessary health care issues before he's allowed to go out the door with you. (This by no means is the way every shelter operates.)

Organizations that operate this way pick up the cost of spaying or neutering, vaccines, and medical treatment and appreciate additional donations if the dog required significant medical care. (Or even if he didn't--they always need more money.) Your adoption fee for a healthy dog helps cover expenses for dogs needing more care.

The adoption process

Each organization has its own adoption process and forms, but the basics are similar. The best and most responsible among them do their best to see that you provide a good home. So don't be surprised if a humane shelter or rescue group is as rigorous in assessing you as you are in checking out the dogs.

• Select the dog(s) you'd like to meet on the website, at a public event, or during a visit to the shelter.
• Bring proof of home ownership or proof of landlord approval for pets.
• Meet with an adoption counselor.
• Meet the dogs.
• Fall in love.
• Ask for a cat test if you have a cat or plan to have one living with the dog.
• All people, and sometimes pets, who live in the home will meet the dog in question, cutting down on the risk you'll want to return the dog.
• Pay the adoption fee and sign papers.
• Wait whatever period of time the organization requires, and then bring a leash, and a good home, to your new best friend.