An irrigation system is disclosed, useable e.g. for rectal/anal irrigation. The system comprises a reservoir for irrigating liquid; a probe (such as a catheter) for arrangement in a user, and having an inflatable retention member (such as a balloon); and tubing providing fluid communication between the reservoir, the control unit and the probe for conducting the irrigation fluid from the reservoir to the probe. Further, there is provided at least one pump for pumping gas into the reservoir to transfer the irrigating liquid from the reservoir to the probe for irrigation and for inflation of the inflatable retention member. Still further, a control unit is provided, comprising separate control elements for operating the at least one pump for irrigation and for inflation and/or deflation of the retention member, respectively, wherein said control elements are operable independently of each other.