The Kālacakra Tantra was the last Buddhist tantra to appear in India, before the disappearance of Buddhism there, roughly a thousand years ago. This is the third book on Kālacakra by Vesna Wallace. We must be very grateful to her for another helpful contribution to our knowledge of this complex system. Her first one, The Inner Kālacakratantra: A Buddhist Tantric View of the Individual (New York, 2001), provides an overview of the whole system, drawing on all five chapters of the Kālacakra Tantra. Her next one, The Kālacakratantra: The Chapter on the Individual together with the Vimalaprabhā (New York, 2004), presents a translation of the second chapter of the Kālacakra Tantra along with the indispensable Vimalaprabhā commentary thereon. The Kālacakra Tantra is written entirely in the sragdharā metre, in which the length of every syllable is regulated. When a complex system is presented in a complex metre, we have a text that is hard to understand in the extreme. It would be almost incomprehensible without the full and detailed Vimalaprabhā commentary.