A control system for a thermoregulation assembly, including: a fluid manifold assembly including a manifold input for receiving thermoregulation fluid from at least one source of thermoregulation fluid at a thermoregulation temperature, and a manifold output for supplying thermoregulation fluid to an interface pack; the manifold assembly being operable to selectively provide thermoregulation fluid into a said interface pack via the manifold output in accordance with feed parameters; a control unit operable to obtain a characteristic energy transfer rate between a first user and a first such interface pack before a treatment plan is commenced, and to obtain a desired temperature profile and a conversion algorithm, the desired temperature profile providing a profile of desired interface pack temperature over time for the treatment plan and the conversion algorithm providing a formula for deriving one or more feed parameters for bringing the first interface pack to or maintaining the first interface pack at a desired temperature, the conversion algorithm being dependent upon the characteristic energy transfer rate; wherein the control unit is operable to calculate one or more feed parameters from the desired temperature profile and the conversion algorithm; wherein the control unit is operable to operate the fluid manifold assembly in accordance with the said one or more feed parameters; wherein the characteristic energy transfer rate is a difference between an absolute energy transfer rate of the first interface pack when applied to the first user, and an energy transfer rate of the first interface pack without a user. a fluid manifold assembly including a manifold input for receiving thermoregulation fluid from at least one source of thermoregulation fluid at a thermoregulation temperature, and a manifold output for supplying thermoregulation fluid to an interface pack; the manifold assembly being operable to selectively provide thermoregulation fluid into a said interface pack via the manifold output in accordance with feed parameters; a control unit operable to obtain a characteristic energy transfer rate between a first user and a first such interface pack before a treatment plan is commenced, and to obtain a desired temperature profile and a conversion algorithm, the desired temperature profile providing a profile of desired interface pack temperature over time for the treatment plan and the conversion algorithm providing a formula for deriving one or more feed parameters for bringing the first interface pack to or maintaining the first interface pack at a desired temperature, the conversion algorithm being dependent upon the characteristic energy transfer rate; wherein the control unit is operable to calculate one or more feed parameters from the desired temperature profile and the conversion algorithm; wherein the control unit is operable to operate the fluid manifold assembly in accordance with the said one or more feed parameters; wherein the characteristic energy transfer rate is a difference between an absolute energy transfer rate of the first interface pack when applied to the first user, and an energy transfer rate of the first interface pack without a user.