We present observations of the 35- to 1600-keV proton intensity--time profiles and the three-dimensional 35- to 56-keV anisotropy distributions recorded during two interplanetary shock events on ISEE 3, and discuss these in the light of current particle acceleration models. The large April 5, 1979, event associated with a quasi-parallel shock shows an extended foreshock region with a strong increase of the upstream proton flux, a downstream plateaulike profile, upstream flow from the shock, and downstream isotropy in the solar wind frame of reference. The small March 9, 1979, event has a structured intensity-time profile, a narrow shock spike, and anisotropic angular distributions both upstream and downstream, the anisotropies immediately behind the shock exhibiting an intensity peak at pitch angles around 90¿. The April event, representative for a class of large energetic storm particle events, shows many observational features which are in agreement with predictions made by diffusive shock acceleration models. The March event, representative for a class of events with irregular profiles and mainly associated with quasi-perpendicular shocks, exhibits features which are characteristic of shock drift acceleration. We conclude that both acceleration models are operative in association with interplanetary shocks.