Six general introductory chapters summarize the physics and biology of the radioactive isotopes now used in therapy. Of these, the fifth, on the production and handling of these extraordinary materials, is especially necessary reading for the physician. Subsequent chapters deal with various modes of administration (for instance, the intracavitary use of radioactive colloids ), with particular isotopes ( teletherapy with cobalt=60), and with particular diseases (leukemia, prostatic carcinoma, and thyrotoxicosis). The information is copious, concrete, and clearly stated, and the editing has been so skillful that the reader is quite unaware of the multiple authorship. The illustrations and index are excellent. The book is highly recommended.