Our highly valued colleague, inspirational mentor, friend to many, effective teacher, and enthusiastic promoter of the science of cytometry has sadly left us forever. As the initiator of the Cytometry journal, Zbigniew Darzynkiewicz has bequeathed a weighty legacy of scientific knowledge founded on careful experimentation and highly cited publications. He was Editor to Cytometry and later Cytometry Part A from the very first issue. Zbigniew shaped the journal and the field of cytometry for over four decades . He helped hundreds of young scientists to improve their own studies and adopt methodologies he created. His contributions to our discipline continue to be built upon by his students and those who have benefitted from his scientific curiosity. He will not be forgotten.