They don't run THAT big
I heeded other reviewers advice and since I wear a 7, I went for the 4/5. Turns out two sizes down is way too small. My heel is hanging off the end of this flip flop. I'll have to return the other pair I got and go a size up, since I've already cut the tags off this pair and can't return them. At over ten dollars a pop for flip flops, that's a pretty huge mistake. Do get a size smaller, but don't get two sizes smaller. (And yeah, even at about half a size to a size too small, I can tell how comfortable they'd be if they actually fit.)

comfortable and a good price!
I wear these for the shower at my dorm and to walk around. So far they are very comfortable and seem very durable. I recommend buying them.

They run big!
I haven't actually worn these shoes, yet, as it is still winter, but I did try them on and they are a pefect fit. I took the advice of other reviewers and actually went down 2 sizes! I normally wear an 8-8 1/2. These are a USA 6, BRA 37/38, EUR 39/40. They seem comfortable and fit like a glove! I did see these in Von Maur recently, a local upscale department store, so if you are worried about ordering online for fear of having to pay to send them back due to sizing, call your larger depatment stores and see if they carry them. These are very casual, but Haviana does make some that are shimmery and some that have thinner straps if you are looking for something to wear with a dressier/casual outfit.

I love Havaianas
When I need to throw some shoes on in a hurry,
I always go for my Havaianas. Fortunately, I live in a warm climate. I have four pairs. They never wear out and are amazingly comfortable.

Comfy and Chic
These slippers are awesome! They're made from a soft (but not squishy) rubber and are very comfortable to wear. However, I agree that these run big. I am usually a 7.5-8 and I ordered the 6-7 (37/38), which fits perfectly. I ordered these in brown, and I'm very happy with my choice. They go well with many different outfits, particularly since the style of the slipper is very basic. I've seen others sporting the bright colors, and they're also very cute, although less versatile. I'm tempted to buy the white one, too, but I've seen those get very dirty!