Disclosed is a method for establishing a telecommunications link (C1, C2, C3) for a user to whom a first communications terminal (D1) is allocated. According to said method, an allocation information is made available to a control program (100, 22) running on a CTI server (20) for establishing the telecommunications link (C1, C2, C3), in which information a first allocation (72, 92) is defined for the first communications terminal (D1) as specified by the user, said first allocation defining an allocation of a second communications terminal (D3, D4) to the first communications terminal (D1). The telecommunications link (C1, C2, C3) is established by the control program (100, 22) in accordance with the first allocation, using the second communications terminal (D3, D4) instead of the first communications terminal (D1). The method is characterized in that in the allocation information a second allocation (70, 90) is defined, by which the first communications terminal (D1) is signaled to the control program (100, 22) as being the only terminal used by the user in the telecommunications link established (C1, C2, C3). The invention further provides a corresponding system.