Theoretical and experimental studies were made on two classes of buoyant jet problems, namely: an inclined, round buoyant jet in a stagnant environment with linear density-stratification; and, a round buoyant jet in a uniform cross stream of homogeneous density. Using the integral technique of analysis, assuming similarity, predictions can be made for jet trajectory, widths, and dilution ratios, in a density-stratified or flowing environment. Such information is of great importance in the design of disposal systems for sewage effluent into the ocean or waste gases into the atmosphere. (Modified author abstract)