The relationship between the 4D folding of the genome and its function is an outstanding question in biology. A range of methods that probe the folding of the genome in space and time with unprecedented resolution have been developed. These methods, including chromosome conformation capture and high-resolution light and electron microscopy, are shedding new light on genome architecture and function. Here, we review the emerging picture of genome organization revealed by super-resolution and live-cell imaging. We compare and contrast population-based chromosome conformation capture approaches and imaging-based approaches and highlight future challenges.