Development of novel treatments for cancer will be dependent on the ability to modulate cellular pathways that are aberrant in cancer cells as well as the capacity to deliver therapeutics effectively to the tumor. Chemotherapeutic regimens are determined primarily by maximum tolerated dose not the maximally effective dose for antitumor efficacy. Our ultimate goal is to deliver higher concentrations of chemotherapeutic agents to target cells where they are cleared at a slower rate while reducing the concentrations encountered by other organs compared to the standard delivery methods for the same chemotherapeutic agent. To accomplish this, we are generating panels of tumor-specific peptidic ligands that can be incorporated into different drug delivery systems. We are exploring direct conjugates of chemotherapeutics and cytotoxins with the peptides as well as incorporating the peptides into drug delivery vehicles such as liposomes, micelles, and biodegradable polymers.