Advancements in fuel spray injection systems for internal combustion engines and other fuel combusting systems require new tools and methods to produce sprays, to study their properties, and to quantify details such as local droplet size, droplet velocities, droplet concentration, and droplet temperature. Direct quantities, on which spray formation depends, need to be measured, rather than quantities olt which an indirect dependence exists. At the Institute of Fluid Mechanics of the University of Erlangen-Nurnberg, research and development work has been carried out on spray systems, yielding new methods, tools, and instruments to produce and study sprays. A summary of this work is given in this article, providing information on: A new method to measure the instantaneous flow rate through the supply line of an intermittently operating fuel injector An innovative method to produce sprays of controlled sized distribution using vibrational excitation to support the spray formation An optical system to measure the velocity of the spray-producing jet or spray-producing film and the wavelengths of the instability waves that cause the disintegration A simple test facility to study the overall performance of multihole injection nozzles A phase-Doppler system suitable to provide droplet data correctly, including droplet concentration and droplet temperature In this article, the development work is summarized and applications of the measuring techniques are demonstrated. Demonstrations of the developments mentioned above are also provided, and applications to multihole injection systems permitting controlled production of sprays are described.