A set of commerically available seawater-resistant hot wire sensors has been used to measure velocities, turbulence intensities, and Reynolds stresses with spatial resolutions between 0.4 and 5 mm and 3-dB frequency response of 18 Hz. During tests and actual measurments, each exceeding 1000 hours in seawater, mostly with suspended sediments, slimes, bacteria, and algae, experience has been obtained since 1973 on long-term stability, sensitivity, repeatability, directional resolution, permanent seawater exposure, contamination, and corrosion. Ruggedness and performance of metal-clad hot wire probes under shallow and deep-sea conditions up to 69-MPa (10,000 psi) pressure indicate that hot wires can be built to work well in the ocean.