Although machine learning and use of machine-learned models are a technology that will revolutionize medicine and provide more opportunities to improve health outcomes, I was disappointed that none of the articles in the recent CMAJ series on the subject discussed what is known to be a major, and topical, issue with algorithms and machine learning — that they replicate social biases that exist in the systems they are supporting. If biased data are used, then biased algorithms follow. Populations that are over-or underrepresented in data will experience the continued marginalization and failure of machine learning.