Is an Italian Greyhound a good companion for another small dog for example a Boston Terrier?

Any breed of dog can be a good companion to another dog. However Greyhounds are used for running and they love it, so if your dog is into running I suggest you get another Greyhound. If your Greyhound is just a pet then even a small dog or cat would be a good companion. I always own two dogs to keep each other company. I have a white Bichon Frise female and a male Cockapoo 16 months old. They play all the time or just sleep together and I also have a 10 year old cat that thinks she's a dog and has fun with the dogs. They even sleep together!