Mode identification from line-profile variations

We review the current status of different mode-identification techniques based on observed line-profile variations. Three basic methods are currently available to identify the non-radial pulsation modes. These three methods are described, together with their different variants. We further present applications to real data, focusing especially on delta Scuti stars. After having discussed all the methods and their applications, we present an inventory in which we compare the properties of the different methods. Finally, we end with future prospects, both on the theoretical and observational side.