It is now evident that NK cells kill bacteria, fungi, and parasites in addition to tumor and virus‐infected cells. In addition to a number of recent publications that have identified the receptors and ligands, and mechanisms of cytotoxicity, new insights are reflected in the reports from researchers all over the world at the 17th Meeting of the Society for Natural Immunity held in San Antonio, TX, USA from May 28 through June 1, 2018. We will provide an overview of the field and discuss how the presentations at the meeting might shape our knowledge and future directions in the field. Mechanisms of microbial killing by NK cells is rapidly providing novel insights in host defense as well as informing strategies for tumor cytotoxicity.