C-type lectin domain family 4 member N (CLEC4N), also known as Dectin-2, is a C-type lectin expressed by dendritic cells (DCs) and macrophages. Members of the C-type lectin domain (CTLD) superfamily are metazoan proteins functionally important in glycoprotein metabolism, mechanisms of multicellular integration and immunity. They share a common fold and are involved in a variety of functions, such as generalized defense mechanisms against foreign agents, discrimination between healthy and pathogen-infected cells, and endocytosis and blood coagulation. Genome-level studies on human, elegans and melanogaster demonstrated almost complete divergence among invertebrate and mammalian families of CTLD-containing proteins (CTLDcps). The vertebrate CTLDcp family was essentially formed early in vertebrate evolution and is completely different from the invertebrate families. The composition of the CTLDcp superfamily in fish and mammals suggests that large scale duplication events played an important role in the evolution of vertebrates. Dectin-2 is important in host defense against C. albicans by inducing Th17 cell differentiation. Dectin-2 constitutes a major fungal pattern recognition receptor (PRR) that can couple to the Syk-CARD9 innate signaling pathway to activate DCs and regulate adaptive immune responses to fungal infection.