An extensive program of ongoing field, laboratory, and numerical investigations into the characteristics of wave impacts is described and early results presented. Shock pressures are found to be highly localized, both spatially and temporally, able to propagate into cracks and, in freshwater at least, capable of reaching surprising intensities. Conventional scaling of 1:4 hydraulic model data implies that ocean waves approximately 4m high could generate heads in excess of 1000m. Attention is drawn to the probability that, in practice, such extreme pressures may be constrained by the acoustic (water hammer) limit. The parameter map (Allstop & Kortenhaus, 2001) used for predicting impacts is shown not to be entirely reliable and preliminary results of the numerical models are discussed.