I read that these cossies are usually a very tight fit and one should size up, so I was not quite sure what to order. Usually I downsize in order for a tight fit, but here I was worried it would be too small. In the end I still took the risk and took a size smaller (32) than my normal size (34). I am 172cm tall and have a swimmer build with a large ribcage... size 32 fits perfectly and is tight like I love it! However, the straps are quite close to the neck and could start rubbing after a few swims. Overall, very happy though!