[en] Experiment 791 is located in the B5 neutral beam at the Alternating Gradient Synchrotron at the Brookhaven National Laboratory. The spectrometer combines precise tracking with good particle identification capability. The excellent mass resolution (σ = 1.4 MeV) of the spectrometer can be seen from reconstructed K_L → π⁺π^- events. High rate capability is achieved by fully-custom high speed front-end electronics, a massively parallel readout architecture, and a multi-level trigger system. The progress on E791 can be broken into two categories: the completion of the analysis of data taken in 1988 and publication of those results and the completion of a major data taking run in the early part of 1989. These will be discussed separately in this report. 6 refs., 5 figs