If choosing a dog from a shelter, take every opportunity to learn as much as possible concerning any behavioral problems the dog may have. Dogs usually require a greater commitment of time and resources than cats, birds, rabbits, or pocket-pets. Participating in obedience classes with a dog seems to enhance lifelong compatibility, probably by shaping the behavior to be more conducive to living with humans. Dogs need companionship and interaction, and some enjoy and even require regular structured activities, such as walks, games, and agility training. The social interactions and needs of dogs for partnership, while rewarding for many families, may be a bit of a burden for some people who may prefer caring for a cat or bird.
Small dogs tend to be more active and excitable than larger ones.
Thus, while it is tempting to think a small dog is easier to manage than a large one, the temperament of a small dog may be more challenging than many larger breeds. Nonetheless, older people may feel more confidant of not being inadvertently knocked over by a small animal, and small dogs take up less space in a tiny apartment. In general female dogs are likely to be less aggressive and more trainable than males. Someone selecting a breed with more aggressive tendencies might choose a female to reduce the likelihood of behavior problems, or could also consider a more compliant breed, one unlikely to challenge the owner for dominance. This problem prevention approach is very important in increasing the likelihood of a compatible relationship.