We present an MTCMOS switch cell power network design approach from a flow perspective. It begins with switch cell configuration exploration during the floorplanning phase. High-level area, congestion and IR-drop tradeoff is made during early design flow. At the chip implementation phase, the switch cells are further optimized by cell sizing and optimization to meet IR-drop and power dissipation targets. Finally, ECO operations are applied near the end of the design flow to accommodate late-stage design changes. This design approach allows for a graceful convergence of MTCMOS switch cells in power network design and reduces uncertainties and iterations during the flow. This is similar to the timing convergence flow that is currently a standard practice in every chip design. We showed, with experimental results, that this was an effective methodology to design power networks with MTCMOS switch cells.