Which device is responsible for adding the label to an MPLS packet?

The provider edge (PE) router is responsible for adding the MPLS label to a packet. The customer edge (CE) router is passed the MPLS packet with the label stripped off. The customer premise switch is the customer's local switching device and has no relation to MPLS. The term label switch router (LSR) is used to describe the internal switching of the MPLS network.