Topics in Meson Spectroscopy *

Meson spectroscopy is an extremely broad subject, covering ππ scattering with √ s < 1 GeV to the heaviest bb̄ states with masses greater than 10 GeV [1,2]. The goal at both ends of the energy scale is to understand QCD in the nonperturbative regime. It is impossible to do justice to such a large body of work in a short talk so I restrict myself to a few selected topics. Many other aspects of meson spectroscopy are covered in other contributions where the interested reader can obtain a more balanced view of recent developments. In a very short period of time, the subject of heavy quarkonium has come to the forefront. This is the result of two recent developments; the CLEO collaboration is taking data at the Υ(3S) and Υ(2S) which will exceed the world’s existing data by a large factor and the B-factories have observed a number of charmonium states in Bdecay [3,4,5] culminating in the discovery of the η c in B → η cK by the Belle collaboration [3]. These measurements have led to the hope that some of the missing charmonium states may also be observed in B decay. Simultaneously, there has been great progress in Lattice QCD [6] so that we have progress on both the experimental and theoretical fronts. On a second front there continues to be vigorous discussion about the structure seen in ππ S-wave scattering below 1 GeV. My impression is that a consensus is emerging among workers in