Cancer vaccines are intended either to treat existing cancers (therapeutic vaccines) or to prevent the development of cancer (prophylactic vaccines). Both types of vaccines have the potential to reduce the burden of cancer. Treatment or therapeutic vaccines are administered to cancer patients and are designed to strengthen the body's natural defences against cancers that have already developed. These types of vaccines may prevent the further growth of existing cancers, prevent the recurrence of treated cancers, or eliminate cancer cells not killed by prior treatments. Prevention or prophylactic vaccines, on the other hand, are administered to healthy individuals and are designed to target cancer-causing viruses and prevent viral infection. This new book presents important and timely research in this dynamic field.