$KN$ Sigma Terms, Strangeness in the Nucleon, and DA$\mathrm{\Phi }$NE

Expanded and updated version of a talk originally presented at ``IVth Int. Symp. on Pion–Nucleon Physics and the Structure of the Nucleon’', Bad Honnef, 9–13 September 1991, originally published in $\pi N$ Newletter 6 (1992) 21–32. Table of contents:

1. Introduction.
2. $\sigma$–terms and ``measurements’’ of the strange–quark scalar density of the nucleon.
3. Methods of extrapolation to $q^2=t={\omega }^2=0$: a subjective review: 3.1. The improved'' Altarelli--Cabibbo--Maiani method. 3.2. The Fubini--Furlan analysis of meson-nucleus scattering lengths. 3.2. The unitarized’’ version of the Cheng–Dashen theorem.
4. Capabilities for a $\bar{K}N$–scattering experiment at DA$\mathrm{\Phi }$NE.
5. ``Envoi’'.