Helioseismology: Observational methods and requirements

The basic method of helioseismology,i.e. the study of the internal structure and dynamics of the Sun using observations of its surface oscillations, is briefly reviewed. A sampling of some recent accomplishment of helioseismology and its scientific goals is presented, focussing on observational and instrumental requirements. Results and recent improvements related to the instrumental technique being developed in Rome are indicated. Experiments are in progress addressing the measurement ofl = 1 rotational frequency splitting and solarlike oscillations on other stars.