For Publisher’s use CHIRAL LAGRANGIANS ∗ LU TP 01-26

Chiral Symmetry is important in a lot of situations. In this talk I will restrict myself to consequences of Chiral Symmetry for the strong interaction. The subject is very broad as can be judged from the lectures and review articles. In its modern form it was founded by Weinberg and Gasser and Leutwyler. I will discuss a few of the basics in sects. 2, 3, 4. The applications to ππ scattering (sect. 5), some two-flavour results (sect. 6) and resummations, and the question of hadronic contributions to the muon magnetic moment (sect. 7), follow. Some of the theoretical developments in the structure and understanding in particular of the many free parameters follow in sect. 8. Applications to three flavours, sect. 9, quark mass ratios, sect. 10, Vus, sect. 11, anomalies and eta decays, sects. 12, 13, semileptonic, sect. 14, and nonleptonic, sect. 15 weak decays and ǫ/ǫ form the main remaining part. I then conclude by a solar and cosmological as well as a high density application together with some references to neglected areas. More than 300 papers cited one of the three seminal papers in the last two years, obviously necessitating many omissions.