In this week's Nature Biotechnology, a multi-institute team of European researchers presents the results of a study comparing common methods for DNA methylation analysis that are compatible with routine clinical use, providing a resource for the use of such assays for biomarker development and patient care. In their study, the investigators shipped 32 reference samples to 18 labs in seven different countries, where they were analyzed using 21 locus-specific assays and six global assays.