The agency views performance measurement as a process rather than as a series of recurring events. Factors which make performance measurement difficult in the FBI include the length and complexity of the cases it handles, the issue of how it ought to allocate its resources, the problems in implementing integrated national investigative policies, the varying levels of support from the FBI required by other police agencies, and the difficulty of establishing measurement criteria. Weaknesses of the quantitative approach which was popular for some years included the incentives it provided for focusing on less important criminal problems, its bias toward areas capable of quantification, its insensitivity to important qualitative considerations like the magnitude of the offense, and its distorting effect on resource use. Recognition of these weaknesses led to the use of a variety of mechanisms for measurement, including the annual performance appraisal, time use and recordkeeping reports, monthly administrative reports, biannual inspections, program reports, surveys of end users, surveys of users of the FBI's law enforcement services, and scanning of the national print media for references to the FBI. For complex, dynamic organizations like the FBI, any single system of performance measurement will normally be inadequate. Footnotes, one table, and three references are included.