Following Robert A. Charman's previous book Telepathy, Clairvoyance, and Precognition, The Psi Mind in Action explores the extraordinary powers of the human mind in interacting with the physical world in the form of hands-on and distant healing, psychokinesis, poltergeist activity, clairvoyant map dowsing and more. In replicated experiments on mice with normally fatal cancer tumours, the mice that were given healing fully recovered and lived a healthy life whereas those in the control groups died within the expected 14-27 days. Healing has also been shown to inhibit the growth of human cancer cells, accelerate tissue healing, and relieve pain and distress. Multiple EEG studies have found that the brainwaves of patients come into close synchrony with those of the healer during a healing session. Over 50 sociological studies have found that periods of group Transcendental Meditation (TM) have correlated with a reduction in local crime rates and increased feelings of well-being in the community, despite the community being unaware of the meditation activity. Acoustic analysis of wall-rapping sounds made by a 'poltergeist' linked to the mental activity of a young woman were found to have different waveforms from normal physical rapping on the same surface. In another case, the collective mental energy of a group of people trying to create their own ghost instead caused a heavy table to rap answers to questions, move, levitate and even climb stairs. This psychokinetic phenomenon was captured on film and shown on Toronto TV. Other phenomena discussed in this book includes reports of out-of-body observations 'seen' by people whilst unconscious and later independently verified; experiences of the disappearance and reappearance of small personal objects suggestive of a puzzling break in the mind/matter relationship; and a case of a stolen harp found by map dowsing from 1800 miles away. All of these phenomena indicate we need a new understanding of the nature of the mind and its interaction with the physical world. We are not passive observers of the outside world, but are capable of mentally influencing it and changing outcomes. As yet, we have no idea how.