The lymphatic system is a subsystem of the circulatory system central to maintaining tissue homeostasis and immunofunction, including removing excess extravascular fluid, presenting to the immune system foreign bodies and pathogens, maturation of lymphocytes, and absorption of lipid-soluble nutrients from the digestive tract. The lymphatic system consists of an extensive network of lymphatic vessels, lymph nodes, lymph, lymphatic organs such as spleen and thymus, and lymphoid tissues such as tonsils and Peyer's patches. This chapter first gives a brief description of the lymphatic system, followed by a characterization of physicochemical properties of typical drug carriers and their influence on lymphatic uptake and transport, and then reviews the recent development of drug carriers for the lymphatic system delivery with a special focus on nano-scaled particles and their clinical applications in chemotherapy. It also compares alternative administration routes for lymphatic targeting.