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A novel approach in ferroelectric phase shifter designs using BaxSr1-xTiO3 (BSTO) films in a multilayer dielectric environment is described. It is shown that by including a low loss dielectric layer (SiO2) between the coplanar waveguide conductors and the ferroelectric material, significant reduction in the insertion loss can be achieved and as high as three fold increase in the figure of merit (o/dB) is possible to realize. The phase shifter design involves a BSTO thin film over a LaAlO3 substrate for low strain and lattice match. A reduction in the insertion loss by approx. 5 dB/cm for high εr ferroelectric materials, and a decrease in return loss by 20 dB were observed at 10 GHz. Design tradeoffs and fabrication aspects will be discussed.