I normally wear an 8 and so I ordered an 9 and a 10. At first I thought the 9's were too small when I tried to put on the inner boot. So, I put on the 10 and thought wow, this is perfect. Although, they seemed big with the outer boot on. I actually asked Baffin on Facebook about this for size wise and they suggested the bigger. I really did not believe that the 10 was the best fit. I reread the instructions and the fact that the boot is insulated and will conform to your feet. So, I retried the 9's. The inner was snug, but it did not hurt, so I actually tried the boot over it. There were no issues so I tied it up. I ended up using the 9's out in the snow and by the end of the day, they felt like they were about 1/2 size too big!!! They really conform pack down once you get in them!! I am so HAPPY I did NOT get the 10's like I was going to. I would have had my boot falling off. I was able to stuff in sweats AND snow pants into my boot leg AND close it up. My feet seemed to stay warm with a normal pair of socks, although my toes were a tad cool. Not cold, just not as warm. We were playing in snow and ice and there was great traction with no slipping. I feel that they are a sturdy boot and I won't slip out of them and not too big and bulky. I do suggest putting on the inner boot first and then it is much easier to slide into the boot!! :)