The phrase "tight control" refers to having a strong and strict guidance or management over something. It means having a high level of regulation and authority to ensure things are done carefully and precisely. Full definition
Parties have tried to combat this by imposing extremely tight controls on what those speaking on their behalf are allowed to say. (politics.co.uk)
The latter feel obliged to keep tight control over teachers, and they set tasks for them to maintain minimum standards. (educationnext.org)
To conserve resources, some companies will manage risk by keeping tighter control of issues that pose the highest risk to the company and a casual monitoring of minor risks. (rocketlawyer.com)