Over the years, we've had many contractors describe what they believed to be inferior specifications, but it was hard for us to tell if the problem was widespread. To evaluate a broad sampling of concrete specifications, we visited plan rooms in Baltimore, Denver, Detroit, San Diego, and Seattle and did an in-depth review of 50 specifications. Though we saw some well-written specs, sections of many ranged from borderline acceptable to grossly inadequate. Six specification characteristics that didn't receive passing grades include the referencing of ACI documents, making contractors responsible for code requirements, floor-flatness tolerances, specifying air-entrained concrete for hard-troweled surfaces, slump control, and floor-covering requirements for concrete.