Scaling Properties of
High-Energy Diffractive Vector-Meson Production
at High Momentum Transfer

James A. Crittenden

Deutsches Elektronen-Synchrotoron
Notkestrasse 85
D-22607 Hamburg, Germany

The diffractive production of vector mesons in photon-proton reactions at HERA is providing new information which challenges contemporary understanding of diffractive processes and of hadron structure. Following a brief overview of the results obtained from the measurement programs of the H1 and ZEUS collaborations during the first eight years of operation, we will concentrate on the experimental and phenomenological particulars relating to a recent observation of power-law scaling with momentum transfer in semi-exclusive vector-meson photoproduction.