On 20 December, the editors and news writers of Science will announce their selection of the most significant scientific breakthrough of 2018. We invited you to choose from among the candidates and, with some 10,000 votes cast, the four below rose to the top. Now is your chance to decide which of them will be the People’s Choice for Breakthrough of the Year. Voting will close at 11:59 p.m. EST on 12 December. Check back after 2 p.m. EST on 20 December to see how your choice stacks up against ours.