The mucosal-associated lymphoid tissues, including the gut-associated lymphoid tissues, represent a tightly regulated environment that, on the one hand, must resist microbial invasions and on the other hand, when perturbed, causes inflammation such as that associated with inflammatory bowel disease. One type of regulatory cellular subset that has recently gained attention in this compartment is the subset of T cells that are associated with CD1d-restricted responses. Recently, CD1d-restricted T cells have been increasingly appreciated to play a significant role in mucosal tissues of the intestine and lung, for example. In this review, we focus on recent observations in the characteristics of CD1d-restricted pathways in mucosal compartments after a brief introduction to the biology of CD1d and CD1d-restricted T cells.