In a manufacturing planning and control (MPC) system, the shop floor control (SFC) back–end component provides detailed schedule information for each open order in the system. The absence of SFC is evidenced by excessive work–in–progress (WIP) inventories, resulting from excessive slack in scheduling operations. At one client company, the need for shop floor control was judged to be critical, yet the timing of the introduction of a fully integrated SFC was deemed inappropriate due to inadequacies in MPC. Instead, a custom, stand–along, finite capacity scheduler was developed. The package is intended to provide an interim capability only. The package runs on any PC compatible microcomputer, and utilises a user–friendly spreadsheet interface as a front–end. This paper deals with related issues in the design, implementation, and acceptance of a product which provides an interim shop floor control function in a job shop environment. It is seen that organisational issues can have a great impact on progress in the introduction and implementation of new systems, particularly when organisational structure, in this case the use of matrix management, encourages competition for control over the management of machine shop resources.