This specialized volume of Advances in Cancer Research is dedicated to the complex and largely unexplored field of intratumor diversity, with respect to differences in both genotype and phenotype among cell populations within tumors.

• Unique subject matter: there are relatively few previous publications covering this complex topic, even though it has been a matter of much speculation ever since cancers were first studied under the microscope more than a century ago. This volume is an attempt to update the reader on novel findings as well as giving a historical...