This is a preliminary report on the starch iodine method for determining the degree of decomposition in municipal wastes, or compost. All refuse contains starch which must be degraded before refuse becomes a microbiologically stable product. Testing for its presence will indicate whether or not the compost has stabilized. The test is based on the formation of the iodine-starch complex in an acidic extract of compost and has the following advantages: It is rapid and easily performed, it is specific for starch and the equipment is very simple. This is only a qualitative spot test designed to show relative change. After checking satisfactory and unsatisfactory compost with this test, finished compost always gives a characteristic color reaction (yellow); unfinished compost will not. The reliability of the testing procedure can be checked by taking several different samples from the same compost pile and performing the same test on all of them.