This Final Report is issued in two volumes, covering research into the combustion of coal-water fuels. Two separate but related tasks are discussed: Volume I, contains results obtained under Task 1 - ''Fundamental Aspects of Coal-Water Fuel Droplet Combustion''; Volume II describes the work of Task 2 - ''Secondary Atomization of Coal Water Mixtures,''which included experimental measurements in a Spray Test Facility and in the 1 to 3 MW/sub th/ Combustion Research Facility. The processes of devolatilization and char combustion were studied in a laminar flow reactor (LFR) by two experimental procedures. In the first of these, a CWF droplet generator was developed and used to feed CWF droplets directly into the LFR. The CWF droplet generator, which consists of a twin-fluid, internally-mixed atomizer and a series of skimmers to reduce the feed rate of droplets into the LFR, is capable of producing CWF droplets in the size range of 5 to 500 micrometers at feed rates of less than 3 mg/sec. In the second parallel study, solid samples withdrawn from a CWF spray flame, close to the atomizing nozzle, were size graded and fed into the LFR in low particle concentrations. Their combustion history in the LFR was determined by monitoring the intensity of radiation emitted by individual particles during combustion (by two-color pyrometry) and by the use of high speed cinematography. The study has established the importance of rotation induced by the volatile evolution on the break up of coal-aggregates and the release of ash particles. 24 refs., 25 figs.