Quantum computing has entered a compelling scientific era as now quantum algorithms can be run on multiple physical systems. Building even larger machines with error correction is a significant engineering challenge that will require good systems engineering practices. Here John Martinis discusses some scientific and technical strategies and ideas that will be important to consider when transitioning from scientific research to development of a complex engineered system. Also considered will be constraints specific to quantum computers, for example the inability to copy information and the need for complex control systems.