This paper discusses thefractional operator problem, which involves the production of many parts on several parallel machines. In this problem, operators can monitor more than one adjacent machine subject to the operator requirements of the parts being produced on those machines. Thus, the combination of parts being produced determines the number of operators required. We consider minimizing the average setup and holding costs subject to a constraint on the number of operators available. We describe planning- and control-level versions of the problem and give formulations that provide a basis for future work.