Over the past few decades, physicists have learned to cool atoms to lower and lower temperatures and to gain increasing control over them, with exciting and sometimes unforeseen consequences. The payoffs have included atom interferometry, precision spectroscopy, Bose–Einstein condensates (BECs), and even atom lasers. Not surprisingly, experimenters now want to play the same games with molecules. The challenges—formidable enough for atoms—loom even larger for molecules. Nevertheless, a number of groups have entered the quest, with the goal of bringing molecules to submillikelvin temperatures, which are slow enough to be trapped or otherwise manipulated.