The James Webb Space Telescope, perhaps the most significant space telescope of the coming decade, was launched on December 25, 2021, and the first images it has already sent back confirm its remarkable capabilities. But why was it decided that this telescope would “see” in the infrared, and in which areas of astronomical research is it expected to make the greatest contribution? What were the most significant technological challenges that arose during its design and construction, and what innovative solutions did the scientists use to address them?