Diffractive processes in photon-proton interactions at HERA offer the
opportunity to improve the understanding of the transition between the soft,
non-perturbative regime in hadronic interactions at Q2=0 and the
perturbative region at high Q2. Recent experimental results from HERA on
inclusive diffractive scattering, exclusive vector meson production and the
properties of the hadronic final state in diffraction are reviewed. The results
are discussed in the context of current theoretical models.Comment: 7 pages, 7 figure (6 in eps, 1 in ps) talk given at XXXI
International Symposium on Multiparticle Dynamics, Sep. 1-7, 2001, Datong
China URL http://ismd31.ccnu.edu.cn