Phage display is a well-established approach for the identification of bioactive peptides and antibody fragments through the use of high diversity libraries. One major advantage of phage display lies in its ability to rapidly identify target-specific reagents with pharmacological activity as agonists or antagonists. Peptides and antibodies have several clinical advantages over traditional small-molecule chemotherapeutics, including specificity, selectivity and potency. Thus, phage display can be used to generate 'targeted therapeutics', which is the current clinical paradigm of choice in the field of oncology.