A system and a method for emptying an ostomy bag (12) into a collecting bag (14) is disclosed. The ostomy bag (12) is connected to a waste collecting bag (14) by means of a first connector (C1) and a second connector (C2). By a single combined locking and opening maneuver, the user may lock the ostomy bag to the collecting bag such that they stay connected to each other during a subsequent emptying, and open valves in the two connectors (C1, C2) for providing a sealed flow path from said ostomy bag to said collecting bag. By a single unlocking and closing maneuver, the user may subsequently unlock the waste collecting bag (14) from the ostomy bag (12) and close both valves.
