First of all let me say that Brookline actually is a fine place for a dog because it has a good size dog park, (specific but good hours), and also because it is "part of" a wider area where there are many great dog spots: Jamaica Plain, Roslindale,Brookline,West Roxbury. Google The Emerald Necklace; Arnold Arboretum, Millenium Park. Also, Amazon and other booksellers should have some of the books about Boston + dogs. That said,the previous answer is correct about most buildings in Brookline having strict dog (or anti-dog) rules. Brookline is one of the most expensive places to live in Boston area with least sq footage for your buck! I have a dog and live in Jp/Rozzie/WR/Hyde Park area and I am so happy that I do simply bcuz it's so dog friendly without having to be in the suburbs. If you r looking to rent, then with pets u will have less options anywhere u r looking.