Dosing system for the dosing of several fragrances into the steam pipe of steam rooms. The desired aroma is chosen by the user of the steam room by a push-button. The aroma intensity can be set individually for each aroma at the controller. During the dosing of the desired aroma the other aroma pumps are locked. After the lapse of the programme the dosing is locked for 3 minutes. Release of the unit by steam generator or coin automat.