Nano-biotechnology has the potential to impact the detection, treatment and monitoring of cancer significantly and to revolutionize cancer therapies. Nanoparticles are particles with dimensions in the 1-1000 nm range, the scale at which materials have unique physico-chemical and structural properties including ultra small size, large surface to mass ratio, high reactivity, and unique interactions with biological systems. This chapter aims to overview briefly nano-particulate and nanofibrous therapeutic delivery systems based on biocompatible, biodegradable polymeric materials. These multi-functionalized nanocarriers designated as 'magic bullets' as postulated by Paul Ehrlich, the Founder of chemotherapy are presently being developed with the capability of delivering the cancer drugs of interest and bio-imaging for the detection of cancer. © 2013 by Nova Science Publishers, Inc. All rights reserved.