The headline Purchasing Managers Index dropped from 51.7 percent in October to 49.5 percent in November..
The index uses 50 percent as the dividing line between growth and contraction.
A few component indexes showed growth. The new orders index dropped from 54.2 percent to 50.3 percent, holding just above the break-even point. The production index made headway, climbing from 52.4 percent to 53.7 percent.
The inventories index dropped from a sitting-on-the-fence 50 percent to 45 percent. The employment shifted lower, falling from 52.1 percent to 48.4 percent.
The ISM said six of 18 manufacturing sectors reported growth in the month.
The growth industries included petroleum and coal products, paper production, furniture, electrical equipment, appliances and components, food and beverage production, and computer and electronic products.