The Concrete Contractors Association of Greater Chicago has awarded top honors for 1971 to the 27 story reinforced concrete office building at 625 North Michigan Avenue. The Superior Craftsmanship Award, highest of three bestowed, was based on originality in both cast in place design and execution by the concrete contractor. Among technological achievements the judges found noteworthy in the building were the casting of square street-level columns measuring 3 and one-half feet wide by 24 feet high in a single monolithic placing and the use of a steel gang forming procedure in the forming, casting and stripping of the super structure. Another unusual architectural feature was the elimination of structural corner columns to provide open corner windows for executive offices.