Research the breed
My pet was a gift, which my vet frowned upon. She figured since I didn't make the purchase I wasn't going to be committed to the dog's welfare. You've probably guessed from my picture that quite the opposite is true. He's like my son. That's us dressed up in Mets T-shirts for Dog Day at Shea Stadium.
As much as I love my dog, I don't think I would have chosen a terrier, though. Mainly because he's very stubborn. Our walks can sometimes be a real battle of the wills.
Before bringing a pet into your home, carefully research the characteristics of the breed so you can enjoy a pet that will mesh with your lifestyle. The American Kennel Club has a good web site for research.