This paper presents an analytic solution for the flow of a laminar incompressible Newtonian fluid between two parallel circular plates undergoing oscillatory motion. The solution uses an iterative approximation technique and includes both convective and unsteady fluid inertia terms. The extent to which these terms influence the pressure and load carrying capacity for various flow parameters is analyzed. The results show a significant deviation from the inertialess (viscous) solution at low excursion ratio, e, and moderate modified Reynolds number, Reo. For a purely harmonic (sinusoidal) motion of the plates, a steady-state force is generated in addition to the dynamic transient force. This is due to the inclusion of the inertia terms and is shown to be a function of the excursion ratio, e, and another dimensionless parameter, the squeeze velocity number, N.