Normally I would buy a 10W, but reading other reviews about how narrow these shoes are, I ordered a 10WW (2E). That should have given me plenty of toe room, but they're more like a 10M in width. I have another pair of New Balance walking shoes (model WR817) in the exact same size that are a perfect fit. What that tells me is that NB's sizing isn't consistent across all models. But putting that aside, these are wonderful shoes for walking and I can wear them to work with slacks because they look more like an oxford than an athletic shoe. I wear a thinner sock to accommodate the narrower than stated width.