A subsea interface module configured to be coupled to a BOP assembly, the subsea interface module comprising: a first inlet configured to be coupled to and in fluid communication with a first auxiliary line and to permit fluid communication between the first auxiliary line and at least one of a booster line, a choke line, a kill line, and a bleed line associated with the BOP assembly; a first outlet configured to be coupled to and in fluid communication with one of the booster line, the choke line, the kill line, and the bleed line; a second outlet configured to be coupled to and in fluid communication with one other of the booster line, the choke line, the kill line, and the bleed line; and one or more valves configured to control fluid communication between the first inlet and the first and second outlets, the one or more valves being movable between: a first state in which fluid communication is permitted between the first inlet and the first outlet; and a second state in which fluid communication is permitted between the first inlet and the second outlet; and a releasable riser connector configured to be coupled to a riser and to permit fluid communication between the riser and a throughbore of the BOP assembly; wherein the module is configured such that, when the first auxiliary line is coupled to the first inlet and the riser is coupled to the riser connector: decoupling of the first auxiliary line from the first inlet does not decouple the riser from the riser connector; and/or decoupling of the riser from the riser connector does not decouple the first auxiliary line from the first inlet. a first inlet configured to be coupled to and in fluid communication with a first auxiliary line and to permit fluid communication between the first auxiliary line and at least one of a booster line, a choke line, a kill line, and a bleed line associated with the BOP assembly; a first outlet configured to be coupled to and in fluid communication with one of the booster line, the choke line, the kill line, and the bleed line; a second outlet configured to be coupled to and in fluid communication with one other of the booster line, the choke line, the kill line, and the bleed line; and one or more valves configured to control fluid communication between the first inlet and the first and second outlets, the one or more valves being movable between: a first state in which fluid communication is permitted between the first inlet and the first outlet; and a second state in which fluid communication is permitted between the first inlet and the second outlet; and a first state in which fluid communication is permitted between the first inlet and the first outlet; and a second state in which fluid communication is permitted between the first inlet and the second outlet; and a releasable riser connector configured to be coupled to a riser and to permit fluid communication between the riser and a throughbore of the BOP assembly; wherein the module is configured such that, when the first auxiliary line is coupled to the first inlet and the riser is coupled to the riser connector: decoupling of the first auxiliary line from the first inlet does not decouple the riser from the riser connector; and/or decoupling of the riser from the riser connector does not decouple the first auxiliary line from the first inlet. decoupling of the first auxiliary line from the first inlet does not decouple the riser from the riser connector; and/or decoupling of the riser from the riser connector does not decouple the first auxiliary line from the first inlet.