Polyethers are an ubiquitous class of commododity polymers for use in biomedical devices and as the soft segment in polyurethane foams. While isotactic poly (propylene oxide) was first discovered by Pruitt and Badgett in 1949, subsequent efforts to control its molecular weight and dispersity have remained largely unsuccessful. The Coates group developed a first generation of a homogeneous, bimetallic catalyst that offered control over tacticity but poor molecular weight control. In this work, a second generation of bimetallic catalyst was developed in conjunction with the use of alcohol chain transfer agents for the synthesis of stereoblock isotactic poly (propylene oxide). While this catalyst offered moderate control, development of a third generation of bimetallic catalyst gave exquisite control and a living polymerization system. Despite years of catalyst development, the physical properties of isotactic poly (propylene oxide) were poorly understood and were explored with the new generations of catalysts. Having developed catalysts that allowed for the synthesis of targeted molecular weight and dispersities and gained a full understanding of the properties of the homopolymer, we established a system for the precise incorporation of ester units for the synthesis of polyether-polyester copolymers. Although these new generations of catalysts offered unprecedented control, the third generation exhibited an induction period. Unfortunately, the paramagnetic nature of the catalyst complicated characterization of this phenomenon. To gain a better understanding, this period was studied by electrospray ionization. The induction period arose prom adventitious water present in the polymerization solvent. More rigorous solvent drying reduced the observed induction period. Variation of steric and electronic parameters on the catalyst allowed for development of a catalyst with twice the selectivity of the third generation with the same level of control.