enforcement
Making sure rules or laws are followed by taking action.
Enforcement means making sure rules and laws are followed by taking action when they're broken. When a teacher enforces classroom rules, she might give consequences to students who talk out of turn. When police officers enforce traffic laws, they stop drivers who speed or run red lights.
The word comes from enforce, which means to compel or make something happen. Think about a referee in a soccer game: the rules are written in a book, but the referee enforces them by calling fouls, awarding penalties, and making sure both teams play fairly. Without enforcement, rules are just suggestions.
Enforcement can be gentle or strict depending on the situation. A librarian enforcing the quiet rule might give a soft reminder, while border patrol agents enforcing immigration laws have much more serious responsibilities. The key is that enforcement requires both authority (the power to act) and action (actually doing something about rule-breaking).
Schools have enforcement of attendance policies, cities have enforcement of parking regulations, and courts have enforcement of contracts. Good enforcement makes rules meaningful. Without it, people who follow the rules feel cheated, and those who break them face no consequences. That's why most communities need some form of enforcement to function fairly.