Book excerpt: Exciting developments in strategic areas of science and engineering makes for possible new engineered structures identified as quantum metamaterials. These new structures offer unusual properties that involve fundamental concepts such as entangled quantum states, superposition, quantum coherence, analog quantum simulation, etc., opening a new era of technological advancement. This manuscript presents the output of a recent workshop held at the National Institute of Standards and Technology in 2018. It covers the key scientific ideas, various technical approaches under investigation, and the potential technological outcomes in a new field of research.