Electromagnetic processed and the diquark model

The present status of the diquark model for exclusive reactions at moderately large momentum transfer is reviewed. That model is a variant of the Brodsky-Lepage approach in which diquarks are considered as quasi-elementary constituents of baryons. Recent applications of the diquark model, relevant to high energy physics with electromagnetic probes, are discussed: electromagnetic form factors of baryons in both the space-like and the time-like region, two-photon annihilations into proton-antiproton pairs as well as real and virtual Compton scattering. (author)