We present a 2.5-D axisymmetric MHD model to self-consistently describe the formation of a stable prominence that supports cool, dense material in the lower corona. The upper chromosphere and transition region are included in the calculation. Reducing the magnetic flux along the neutral line of a sheared coronal arcade forms a magnetic field configuration with a flux rope topology. The prominence forms when dense chromospheric material is brought up and condenses in the corona. The prominence sits at the base of a helmet streamer structure. The dense material is supported against gravity in the dips of the magnetic field lines in the flux rope. Further reduction in magnetic flux leads to an eruption of the prominence, ejecting material into the solar wind. ¿ 2001 American Geophysical Union