The drugs which are used in the treatment of cancerous or malignant diseases are termed anti-cancer drugs. The different categories of anticancer drugs are antimetabolites, alkylating agents, hormones and natural products. There are some drugs which do not fall within these categories but exhibit anticancer properties. The selection of a particular anticancer drug to treat a cancer depends on various factors such as the severity of cancer, the location and the type of cancer. The side effects of the drug and whether radiation therapy or surgery can be used are also reasons which help in the determination of which drugs should be administered. This book attempts to understand the multiple branches that fall under the discipline of anti-cancer drug discovery and how such concepts have practical applications. It presents researches and studies performed by experts across the globe. Researchers and students in this field will be assisted by this book.