A rack-mountable in-line surge protection system includes a chassis configured to mount to an equipment rack, the chassis including: an electrically-conductive buss, an electrically-conductive ground member coupled to the buss and configured and disposed to be connected to a grounding mechanism, and a plurality of electrically-conductive bias members coupled to the buss. The system further includes surge-protection modules configured to be removably inserted into and coupled to the chassis, the modules each including a printed circuit board and a plurality of receptacles for receiving connectors and coupling the connectors to the circuit board, the circuit boards each including a grounding contact portion and surge protection circuitry, where the chassis and the modules are configured such that the circuit boards are disposed between respective bias members when inserted in the chassis, with the grounding contact portion of each circuit board in electrical contact with at least a respective one of the bias members.