An exhaust gas recirculation cooler, typically of the drawn cup design,
with a bypass and control valve is disclosed. The control valve can
direct a proportion of the exhaust gas to the cooler and a proportion to
bypass the cooler depending on the input temperature of the exhaust gas
and the required temperature of the exhaust gas. The proportion of the
exhaust gas directed to the cooler/bypassing the cooler can be varied as
required and so the temperature of the exhaust gas can be controlled. One
benefit of certain embodiments of the invention is that engine damaging
chemicals, such as sulphuric acid, which result from over-cooling the
exhaust gas are reduced.