Microconductivity probes were used for the measurement of point values of mean concentrations and root-mean-square concentration fluctuations for mixing of salt solutions in turbulent shear flows. Mixing studies covered a range of flow conditions, with Reynolds numbers on the order of 104, and included ducted turbulent iets, dispersion in turbulent pipe flow, a plane mixing zone, and several multiple injection systems. The test sections all had characteristic dimensions of about 2 cm. The results for mixing experiments are compared with available previous work. Lack of resolution for root-mean-square concentration fluctuations in some previous work is indicated.Reaction product concentrations for a rapid, second-order, irreversible reaction in multiple injection systems, the plane jet, and the mixing zone were also obtained. The relation between conversion in reaction experiments and fluctuation level and decay in the equivalent mixing experiments is illustrated.