Equilibrium and dynamic interfacial tensions measured at 20degreesC for 10(-5) M beta-diketo-1-phenyldecane-1,3-dione (I), 2-hydroxy-5-t-nonylacetophenone oxime (II), trioctylphosphine oxide (III), 2-hydroxy-5-t-octyl-acetophenone (IV) and -benzophenone (V), Cu(II) complexes (except for III), and equimolar I + II, were used in conjunction with the Ward-Tordai (J. Chem. Phys., 14,453 (1946)) adsorption model solved (V.B. Fainerman et at., Coll. Surf. A, 87, 61 (1994)) for time t --> 0 and t --> infinity, to evaluate diffusivities Dt --> 0, and Dt --> infinity, cm(2)/s. With toluene as organic phase, 10(6) x Dt --> 0 were: I, 1.61; II, 1.82; IV, 1.86; V, 3.05; and for Cu(II) complexes: 3.56, 2.24, 2.17, and 1.65, resp., whereas 10(8) x Dt --> infinity were: I, 2.65; II, 9.19; IV, 7.69; V, 4.33 and for Cu(II) complexes: 1.58, 31.5, 26.5, and 9.42, resp. With octane, 10(6) x Dt --> 0 were: I, 4.72; II, 12.8; IV, 15.0; V, 11.8 and for Cu(II) complexes: 21.1, 12.5, 14.1, and 13.5, resp., whereas 10(8) x Dt --> infinity were: 178, 769, 22.5, and 16.5, resp. and for Cu(II) complexes 83.2, 2230, 183, 51.2, resp. With 0.001, 1 or 3M HNO3 or M KNO3 addedto water phase, III had Dt --> 0 and Dt --> infinity lower by resp. one and two orders of magnitude from those evaluated with pure water.