The organisational efficiency of sample admission to the routine laboratory and the allocation to test methods has been improved by a scheduling system based on an on-line mini-computer. A flexible system has been constructed using multiple visual displays, which produce work allocation lists. Computer techniques have been developed which enable maximal use of the on-line system while retaining the general flexibility of high-level language coding, as implemented on an unsophisticated 12-bit processor. The file structure has been designed to provide cumulative information on the requesting patterns appropriate to any of the many sources of samples to the laboratory, and to allow the automatic merging of worksheet and laboratory data, the latter being generated and transmitted from a second mini-computer system.