This article is from the Mastiffs Breed FAQ, by mmcbee@access.mountain.net (Mike McBee) with numerous contributions by others.
Indoors, of course. What's the sense of having a Mastiff if
you don't have it close to you? It certainly can't protect
you from the boogie man if it's tied out in the yard. And
it's useless as a footstool if you keep it fastened in a
kennel or locked in the garage.
Seriously, Mastiffs seem to have an instinctive need and
desire to be as close as possible to their human family, to
the point that their emotional development can be stunted if
they are deprived of that closeness. Many breeders will
refuse to sell a Mastiff unless the new owner guarantees that
it will be kept as a house dog.
 
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