Despite increasing attention being paid to the potential harms of online targeting over the last year, there is still a lack of clarity over what precisely those harms are. To help address this lack of clarity, this submission focuses on question 1: What evidence is there about the harms and benefits of online targeting? This question was discussed at a workshop we held on “The Methodology and Ethics of Targeting” at the Leverhulme Centre for the Future of Intelligence in May 2019 (organized by the authors of this submission, and attended by some members of the CDEI). Our submission summarises some of these discussions and attempts to map out some of the key researchers, groups, and publications we know are working on various harms of targeting. This is not intended to be comprehensive, but we hope will help highlight areas worthy of more attention for the CDEI.