Marketing is a core business function in commercial companies but is also frequently used by not-for-profit organisations. Marketing focuses on understanding what people value to make choices about engaging with a product or service: a concept also key to understanding why people may choose to engage with a clinical trial. Understanding the needs and values of stakeholders, whether they are participants, staff at recruiting sites or policy-makers, is critical for a clinical trial to be a success. As many trials fail to recruit and retain participants, perhaps it’s time for us to consider approaches from other disciplines? Though clinical trial teams may consider evidence- and non-evidence-based recruitment and retention strategies, this is rarely done in a systematic, streamlined way and is often in response to challenges once the trial has started. In this short commentary, we argue the need for a formal marketing approach to be applied to clinical trials, from the outset, as a potential prevention to recruitment and retention problems