Here are a few things you should know:

• Yes, they drool. This varies depending on the dog, but some drool and foam up a lot. If you're squeamish about a little saliva, cross bullmastiffs off your list.
  

• Yes, they are big. Males weigh in the neighborhood of 130 lbs, females, 110 lbs. This is a lot of dog. If you are not at least as smart and more stubborn than they are, forget it.
  

• Yes, they are expensive to keep. Veterinary visits, prescriptions, toys and food will have you spending lots of money each year if you're going to care for your bullmastiff properly. Remember that it costs a lot more to medicate a dog that weighs 100 lbs than it does to medicate a dog that weighs 30 lbs.
  

• Yes, they should live indoors. I won't place my puppies with people whose dogs live outside. Bullmastiffs want to be with their people, period.
  

• Yes, most are protective ... but not all. Most bullies are instinctively protective of their home and family.
  

• Yes, they are very affectionate. This is not an aloof breed. Expect to be reminded frequently by your bullmastiff how lucky you are to share your home with a bullmastiff.
  

• Yes, they generally do very well with children. It is always a good idea to teach children the proper treatment of dogs, however, and never a good idea to leave children unattended with dogs.
  

• No, they don't generally like other dogs, especially dogs of the same gender. Bullmastiffs are not pack hounds. They were bred to patrol estates and be on the lookout for interlopers -- human and canine. Don't expect them to get along with every dog they meet, and take care to keep them within your control where strange dogs are about.