This chapter investigates the effect of pulsatility on flow through a tapered artery. Blood has been represented by a non-Newtonian fluid obeying the Herschel-Bulkley equation. Using the Reynolds number as the perturbation parameter, a perturbation technique is adopted to solve the resulting quasi-steady, nonlinear, coupled, implicit system of differential equations. It is observed that the wall shear stress and flow resistance increase with increasing values of the taper angle and the axial distance. The present approach generally has validity over many mathematical models developed by others, and it may be applied to any mathematical model by taking into account any type of rheological property of blood. The obtained velocity profiles have been compared with the experimental data, and it is observed that blood behaves like a Herschel-Bulkley fluid rather than Power-law, Bingham, or Newtonian fluid. Finally, some biorheological applications of the present model have briefly been discussed.