This expanded and revised text includes thirteen experimental reports (5 new to this edition) and seven review articles involving meta-analysis and the assessment of evidence in specific areas of psi research. The author provides a representative sample of the extensive literature in the controversial field of parapsychology and presents a few basic experiments illustrating various procedures and broadly reflecting the major trends of psi research. Possible experimental procedures, cumulative evidence showing the replicability of individual experiments, and promising areas of psi research are also discussed.