An angry customer represents a demanding test for a customer support employee. When a client becomes upset, begins to use harsh words, and their behavior borders on aggressive, the question arises as to how a company representative should respond. On the one hand, the principle "náš zákazník, náš pán“ applies; on the other hand, it is not possible to always overlook a client's inappropriate conduct. The following recommendations suggest how to proceed when a customer becomes angry and abusive.