It's Vogue 1268 by Guy Laroche. You can get the details on the pattern here. The dresses in the previous picture have collars, but that's easy enough to add if you choose. I actually like the cleaner Vogue pattern version better.
Just a quick story. I attended a luncheon a couple of days ago and as I was listening to the speaker, I looked around the room to check out what people were wearing. Horror of horrors, there were two women in the same exact dress!!! OMG!!! And they weren't sitting that far apart from each other. Now, for those of us who sew, aren't we lucky? I always know that I will not see a mirror image of myself. Thank goodness.
Hope you have a wonderful day.