Because the concept and discoveries of cancer stem cells are relatively new, scientists and researchers need an introduction to this dynamic area. Cancer Stem Cells presents a consolidated account of the research done to date and recent progresses in the studies of cancer stem cells. Such a presentation facilitates a better understanding of and draws attention to stem cell and cancer biology, two fields that enhance, move, and evolve into each other continuously. It provides an informative study in designing approaches to apply stem cell principles to cancer biology while offering an overview of the challenges in developing combination stem and cancer biology targets for therapeutics.