The isotope Re/sup 189/ was produced by fsst neutron irradiation of osmium and by the ( alpha ,p) reaction on tungsten. The rhenium was separated chemically from the target material, and beta, gamma, and internal conversion spectra were measured. The mass assignment is confirmed by the observation of eleven electromagnetic transitions in the Os/sup 189/ daughter, including the 30.8-kev isomeric transition (8 hr), all of which were known from the decay of Ir/ sup 189/. Re/sup 189/ has a half-life of 23.4 plus or minus 1.0 hr and emits betaray groups with end-point energies 1000, 780, and 725 kev, and probably others. Results of coincidence measurements lead to some new information about the level scheme of Os/sup 189/ Evidence was found for strong rotation-particle coupling between low-lying K =1/2 and K = 3/2 bands in Os/sup 189/. 40 references. (auth)