Future directions in Dicer research should include: expanding our understanding of Dicer in the biogenesis and regulation of a growing network of endogenous small RNAs, which have interrelated implications for the regulation of complex physiological processes, including cancer; delineating the regulation of Dicer itself, including the causes and consequences of Dicer subcellular localization; and determining the role of Dicer in response to exogenous RNAs, and how this connects to the immune system. Here, DICER1 is linked to cancer.