Engineered nanoparticles have been gaining tremendous recognition in the pursuit of several biomedical applications, including drug and gene delivery, imaging, detection and targeted therapeutics. This chapter illustrates some important aspects of the use of metal nanoparticlepolymer nanoconstructs demonstrated for targeted cancer therapeutics, with an emphasis on the most commonly used and Food and Drug Administration (FDA) approved metallic nanoparticle (gold and iron oxide) based polymer constituents. Also provided is a brief overview of the various analytical and physical characterization techniques that are used to assess the interactions of nanoparticle-polymer constructs with cancer cells, with an emphasis on their biomedical applications.