Broadband electrostatic waves in a frequency range from about 10 Hz to 1 kHz have been observed in conjunction with very large shears in the plasma flow velocity transverse to the ambient magnetic field in the auroral F region. The shears were detected through their perpendicular electric field signatures, which changed by as much as 200 mV/m over distances of only a few hundred meters. Power spectra of the large-scale electric field and density fluctuations associated with the shears are in excellent agreement with previously reported DE 2 satellite observations. At smaller spatial scales, the observed low-frequency waves were very well correlated with the shears, and had amplitudes of about 1--5mV/m for the electric field variations and a few percent for the correlated density fluctuations. Transverse shears can be uniquely related to field-aligned currents through the current continuity equation, and the resulting field-aligned drift exceeds the threshold for excitation of current-driven electrostatic ion cyclotron waves. A numerical simulation of this instability has been used to generate electric field spectra in the rocket frame of reference, and these spectra are similar to the spectra generated from the actual rocket data. Both shear and field-aligned current are discussed as sources of the waves. ¿ American Geophysical Union 1989