Perimeter Mall is one of the closest things for you. It has Nordie's, Dillard's, Macy's, and Bloomie's as the anchors. And most of your mall standards - Anthro, Express/Limited, BR, J Crew, etc.
Other than that, I don't know much about shopping or things to do in the Dunwoody area.
If you have time, you can go to the Aquarium, but it's not really close to Dunwoody.
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