Controlling agency
Read the official ruleThe "controlling agency" is the specific FAA facility responsible for authorizing flights through or within a particular restricted area. This is the facility you'll need to contact if you want permission to enter restricted airspace that has joint-use provisions.
Which facility serves as the controlling agency depends on the joint-use letter established under §73.15 for that specific restricted area. It might be an Air Route Traffic Control Center (ARTCC), a tower, or another FAA facility—it varies by location.
In practical terms, this regulation tells you that there's a designated point of contact for requesting access to restricted areas. Before flying near restricted airspace, check the Chart Supplement (formerly A/FD) or contact Flight Service to identify the controlling agency for that area, then coordinate with them for permission if joint use is available.
*This is a plain-English summary for study only. The official 14 CFR text on this page is controlling — always read the current regulation and consult a CFI.*