Abstract: The present invention provides a process for treating ion exchange resin which includes the steps of firstly introducing a liquor for treating the resin in substantially vertical upflow into a treatment zone in order to produce a fluidised bed comprising the resin and insoluble particulate matter interspersed with each other, and secondly separating the resin from the particulate matter through entrainment of the latter by the liquor being withdrawn from the fluidised bed in a substantially horizontal flow direction. An apparatus for performing the process outlined above is also disclosed.