At least on me, it is REALLY revealing.  I am a C cup and bought a size large.  It fits perfectly, but I am showing WAAAAY more cleavage than I thought I would.  This dress is NSFW, at least on me!  As with everything else I have bought of this brand, the dress is very well made, great quality and is quite flattering.  My husband would love this on me at dinner.  If it were a little bit higher cut, or I had a tub top or something to wear under it, then it would be ok for work with a cardigan.  Or with the top couple buttons of the cardigan buttoned, maybe.  Really, I'm not a prude, but, VAVOOM.