  We present a finite element method for the Stokes equations involving two
immiscible incompressible fluids with different viscosities and with surface
tension. The interface separating the two fluids does not need to align with
the mesh. We propose a Nitsche formulation which allows for discontinuities
along the interface with optimal a priori error estimates. A stabilization
procedure is included which ensures that the method produces a well conditioned
stiffness matrix independent of the location of the interface.
