Book excerpt: African Plant-Based Products as a Source of Potent Drugs to Overcome Cancers and their Chemoresistance: Part One: Cancer Chemoresistance, Screening, Methods, and the Updated cut-off Points for the Classification of Natural Cytotoxic Products, Volume 111 offers an overview of the potential of African medicinal plants as a source of anticancer agents to overcome with an emphasis on cancer drug resistance. Based on the collected data, the book also offers a rational classification basis for the cytotoxic activity of natural products. The general knowledge of state-of-the-art of cancer drug resistance globally and the screening methods for cytotoxic agents are described.This book clearly identifies the best African medicinal plants that could be useful for the development of efficient herbal drugs, as well as the best phytochemicals that could be explored as potential pharmaceuticals to efficiently tackle cancers and their refractory phenotypes. The book appears a unique tool for Scientists for anticancer drug discovery from the exceptional flora of Africa. - Provides the first of its type reference to focus on the potential of African plants as an alternative medicine to tackle cancers and their recalcitrant phenotypes - Analyzes the recorded data to propose a rational basis for the classification of naturally occurring cytotoxic agents - Clearly identifies and discusses plants and phytochemicals that could be useful in the development of new cytotoxic drugs to overcome cancer and cancer drug resistance