Code of Federal Regulations Title 5. Administrative Personnel § 5.300.403 When commercial recruiting firms and nonprofit employment services may be used

(a) The agency head or designee determines that such use is likely to provide well-qualified candidates who would otherwise not be available or that well-qualified candidates are in short supply;

(b) The agency has provided vacancy notices to appropriate State Employment Service and OPM offices;  and

(c) The agency continues its own recruiting efforts.