Whether it's for applications that exploit the ultra-low energy scales, sensitivity, or complexity of quantum systems, quantum mechanics will play an ever increasing role in engineering. In the past decade, the nascent field of quantum engineering has produced quite good devices and clearer proposals for high level operations. What's less clear is what happens in between, in the realm of several interacting, modular quantum devices. In my opinion, tackling this regime will require finding quantum generalizations to electrical engineering concepts and techniques. For example, just as one often uses Kirchhoff's laws rather than Maxwell's equations to analyze electrical circuits, what approximations to quantum electrodynamics are needed to understand networks of quantum devices and fields? I will summarize my efforts to further this engineering perspective on quantum optical, superconducting microwave and mechanical systems. As broad overview of my work, this talk will touch on the quantum switching of a single-atom optical nonlinearity, the design of all-quantum feedback circuits, and fully coherent and lossless superconducting microwave networks for sequential logic and state squeezing. Refreshments will be served after the Colloquium in room 128.