This is a wonderful Zuckerman and Kraus cocktail or dinner suit, dating pre 1950- likely just after 1947 as this suit is very New Look. The suit has soft shoulders, a tiny waist and a peplum and a very full skirt.
Zuckerman and Kraus was the business owned by Ben Zuckerman prior to opening his own company. Zuckerman and Kraus produced very high end suits and coats. The business was closed in 1950.