I'm a solid size nine, with a wide foot, and though I read the review from someone who is size 8 and said that the slipper ran large, I thought I'd be okay with the 8-9.  Alas, it really IS too big.  I'm sure I could have sized down a full size.  As things are, though, since it's all fabric, I can probably take a tuck in the back with strong thread and it should work.  I got the blue 'wool'; perhaps not all models are the same.  I at first thought that perhaps mens' slippers were being sold by mistake, but the size on the sole clearly says 'women".  Other than that, these are nice enough slippers, though there is an seam near the front that could irritate the foot in a smaller size.  I got them at a good price on Prime day, but I don't think these reflect the usual Acorn quality.  I'm keeping because they were inexpensive and I can make them fit, but you might want to look at others if the price on these is over, say, $30.