Collecting clinical efficacy and safety data in multinational randomised controlled trials (MNRCTs) has long been a means to achieve rapid recruitment of sufficient sample sizes in a timely manner. The strengths and weaknesses of this approach have been well explored in the literature. MNRCTs also provide an opportunity to collect health economic evidence, which introduces its own set of challenges. The following editorial provides an overview of special considerations when collecting health economic evidence alongside MNRCTs. It begins with a description of data collection issues at country level, followed by methodological considerations for analysing data, and finally some considerations for the generalisability of results to country-specific reimbursement decisions.