Titles of clinical trials may directly influence whether patients, caretakers, or healthcare professionals will want to obtain more information about the trial. Major clinical trial registries require lay titles (referred to as “brief” or “public” titles) that are under standable to the public. However, devising adequate lay titles is challenging. In this study, we assessed the quality of lay titles from Phase II/III and III clinical trials registered in ClinicalTrials.gov in 2021. Assessments included the presence of recommended elements, use of technical terms, an expert assessment of adequacy and informativeness, title length, and the use of acronyms. A large proportion (72%) of lay titles did not include all recommended elements, contained technical terms (73%), and were not adequate according to experts (51%). Often, brevity was given precedence over content and understandability. Generally, lay titles with acronyms had better ratings in all assessed categories. These results suggest that industry sponsors can do more to create lay titles that better inform patients and healthcare providers. Medical Writing. 2023;32(1)38-44. https://doi.org/10.56012/lnhw1492