Solar flare dynamics are reviewed as revealed by the X‐ray Bragg Crystal Spectrometer (BCS) package and the Soft X‐ray Telescope (SXT) on theYohkohspacecraft. Doppler motions are detected by BCS as spectral line intensity asymmetries. Motions can be detected by SXT by studying time sequences of images. High speed upflows (400–800 km s−1) are correlated to within a few seconds with the onset of hard X‐ray bursts. However, for most flares a strong non‐Doppler shifted (stationary) spectral line component exists even at flare onset, which is not predicted by standard 1D numerical simulations of chromospheric evaporation into a low density coronal loop. In about 10% of all flares, an intense blueshifted component is present at flare onset. These flares appear to be morphologically complex, but this conclusion is based on poor statistics. The blueshifted plasma shows a longitude dependence, consistent with radial flow. Low speed upflows (<100 km s−1) appear to occur in some instances before the onset of hard X‐ray bursts. In some cases flare loops appear to either twist, expand, or have footpoints that shift in position after the flare rise phase. These motions are slow, e.g., <50 km s−1. As found from previous missions, during the rise phase of flares, line profiles also reveal nonthermal Doppler broadening that decreases during the rise phase from about 200 km s−1to 60 km s−1or less. ©1996 American Institute of Physics.