Three very different task/ambient conditioning (TAC) systems were investigated in a climate chamber. Two desk-mounted TACs, the "Personal Environmental Module" (PEM), intended for US offices, and the "ClimaDesk" (CDESK), intended for European offices, were compared experimentally with a floor-mounted unit, the "Task Air Module" (TAM). All three provide some individual control of cooling, while PEM and CDESK also provide individual control of heating. They were installed with floor-ducted supply air (19-25°C) in standard office cubicles in a climate chamber, and their effect on the heat loss from a 16- section heated thermal mannequin was measured at various room temperatures (19-25°C). The individual control provided by each unit, in terms of the change in room air temperature that would have affected whole-body heat loss equivalently, was PEM: 9K, CDESK: 3K, TAM: 5K. The "thermal asymmetry" caused by each unit is given as the rate of heat loss from each body section.