Tunneling and point contact spectroscopy show clear phonon features and together with optic measurements give strong support that the electron-phonon interaction (EPI) is large inHTSoxides. Strong correlations inHTSoxides renormalize theEPI(and interaction with impurities) so that the forward scattering peak (FSP) develops for small hole doping&dgr;≪1.TheFSPmechanism explains important properties of the normal and superconducting state. ©1999 American Institute of Physics.