Abstract: I will describe my lab’s recent progress in demonstrating and controlling quantum phenomena in single molecule junctions. Our past and future efforts are focused along two complementary directions. First, we work to demonstrated how synthetic modification can be leveraged to create functionality, such as quantum sensing, switching and high conductance of topological electronic states in molecules. Second, we develop chemical design principles for in situ assembly of quasi 1D molecular chains containing transition metal atoms with increased degrees of freedom. This work lays the foundation for our future advances in realizing and characterizing quantum phenomena in molecular circuits.