Metaphorically, antibodies can be described as unarmed guided missiles, which have extraordinary precision and targeting abilities, but once they hit the target, they inflict minimal damage. Chemotherapy and radiotherapy can be described as artillery, very powerful, but unguided. In order to optimally use the two, the most logical step is arming those unarmed missiles with a variety of explosives. Using the same reasoning, there is a true need to develop anti-cancer therapies which have an antibody-like specificity as well as chemo/radio-therapy-like potency. Doing so enables us to take advantage of the selectivity of antibodies and the potent toxic activity of chemo/radio-therapy, thus creating superior cancer treatments. The antibody binds the target on the tumor, delivers its payload and kills the cell. Arming antibodies with effector molecules like chemotherapy agents and radio-isotopes results in a hybrid agent referred to as an Immunoconjugate. An antibody which is not conjugated to an effector is referred to as “naked” antibody.