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The flow properties were measured for concentrated n-butylbenzene solutions of well-characterized linear mono-and polydisperse polystyrene and polybutadiene, four-arm-star branched polystyrene and polybutadiene, and linear and four-arm-star branched random and block copolymers of styrene and butadiene. Concentrations varied from about 100 to 600 kg/m3. Polymer molecular weights varied from about 3 X 104 to 2.5 X 106. The viscosity and first and second normal stress difference functions of the shear rate, (i¡(y), Ni(y), N2(y)), and related steady-state shearing functions extending into the shear thinning region, and the unsteady shearing functions were determined in cone-plate shearing. The "zero" shear viscosity, 0, for linear polymers in the entanglement region was proportional to the entanglement density, E, to the 3.5 power. With the exception of the block copolymers, ij0 for the branched polymers was proportional to (gE)3S. The ratio N2/N1 was -0.29 for all linear-polymer data and -0.214 for all branched-polymer data with a standard deviation of less than 2%.