This article reviews recent findings on expression and function of connexin proteins-the structural subunits of gap junction intercellular channels in the lymphatic vasculature-both during development and in the mature lymphatic vessel. Highlighted in particular are recent mouse connexin knockout studies which show that connexins are crucial for normal lymphatic development. We discuss, in general terms, both channel-dependent as well as channel-independent functions of connexins and raise some of the many unanswered questions about the mechanism (s) of action and physiological roles of connexins in the lymphatic vasculature.