Determinations of Mass Loss Rates

The aim of this paper is to discuss the different methods that are currently being used to estimate the mass loss of stars. In general, two classes of methods can be distinguished: (1) those that use molecular radio line emission (e.g., CO and OH), and (2) those that use the dust emission (dust shell modeling, IRAS 60-micron flux densities, IRAS F25/F/12 flux density ratios, Salpeter relation). The results from individual methods are discussed and compared. Methods to determine mass loss rates as a function of time are also discussed together with interruptions of mass loss which occur during and at the end of the AGB.