The unfoldment of shakti, the power inherent in the core of our being, is the key to all worldly and spiritual success. All spiritual traditions, particularly tantra, aim at awakening this dormant power within us. Because it is so vital to our inner growth, without having an in-depth knowledge of the role of shakti, the study and practice of any spiritual tradition is like farming barren ground.The subject matter of this work, while seemingly focused only on shakti, nevertheless opens doors to a vast range of tantric philosophy and practices. It clarifies how tantric philosophy and practice unify the concepts of yantra, mandala, mantra, chakra, kundalini, deities, and ritualistic and meditative practices. It also explains the relationship among the different branches of tantra and tackles the controversial issues concerning the right-handed and left-handed tantric practices.