I suffer from flat feet and plantar fasciitis, and these are the only pair of sandals I have ever found to combat the pain I get from walking. They are hands down the most comfortable shoes I have ever worn, and never in my life have I been able to wear sandals until finding these. I was always relegated to wearing my insoles with a full shoe, even in the summer, but not anymore. I hope Merrell continues to produce other styles with the combination of the arch, the heel cushion and the Q-form, because the three of them together are amazing in a sole, and I now have 3 pairs of Merrell sandals because of it. I sized up what I normally wear in a shoe with no socks on, and they fit perfect.