Recruitment and retention in cancer trials are long-standing issues, exacerbated by the COVID-19 pandemic. The UK National Institute of Health Research and leading clinicians have emphasised the urgency to achieve and surpass prepandemic levels of participation.Data from a recent UK trial demonstrated the impact of COVID-19 and highlighted factors that limited recruitment. In response to this worldwide problem, studies have identified strategies for remediation at the levels of funding, the research environment, study design and trial team-related aspects, yet evidence of progress is lacking.Equality, diversity and inclusivity have become central to UK health and social policy during the 2000s. The need for greater inclusivity in trials has become a particular concern for cancer researchers and funders in the UK and in the USA, in recognition of potential bias in results. In the UK trials, the lack of standardised recording of ethnicity data renders interpretation difficult and caution is required in comparisons with the USA.Recently, the focus of concern has shifted away from the impact of deprivation and low socioeconomic status on trial participation. Barriers created by these factors and their frequent intersection with ethnicity should not be overlooked.The UK has adopted an advisory approach to broadening recruitment, publishing policy documents, guidance and toolkits. In the USA, by contrast, action on inclusion is increasingly mandated. Within the UK paradigm, the cancer research community is strongly encouraged to adopt a coordinated approach towards standardised digital data collection and embed and evaluate innovative, cocreated, locally relevant strategies.