dryers are intended to operate in a manner in which energy is saved and laundry is treated gently . to this end , it is necessary to regulate the drying process in an optimum manner on the basis of the drying parameters and to find the time point for terminating the drying process which is most favourable for the laundry in question . the invention makes provision for at least one factor to be formed from a plurality of drying parameters and for the drying process to be terminated and / or for the drying process to be regulated on the basis of this factor . the factor can be formed by computer from a few drying parameters which are easy to detect , and regulation can be carried out in a simple manner with little expenditure on the basis of the factor by way of simple comparison with a setpoint value .