An extraordinary conference on cell-free DNA (cfDNA) and its applications with an even more exceptional guest, especially Professor Dennis Lo, who discovered cfDNA, took place in Olomouc (7-8 March 2024). Several of our colleagues not only had the honour to meet him in person but also to present and discuss the important findings of cfDNA involvement in the pathogenesis of diseases such as rheumatoid arthritis, liver diseases, metabolic syndrome or its characterization during sterile inflammation.