"The Bridge of Quiescence" is an excellent detailed discussion of the basic meditation technique of all schools of Buddhism, and even some non-Buddhist approaches. "Quiescence" refers to tranquility meditation, a way to attain a stabilized mind. The "Bridge" part of the title refers to the role of "restful attention" as a necessary basis for further spiritual development. The central chapter offers a translation from Tsongkhapa of the Gelungpa School of Tibetan Buddhism. This could be a tough slog but Wallace provides his own very helpful interpretation, sometimes making reference to Western psychology. So this book is definitely not an introductory text. But for those with some familiarity with meditation in general and Tibetan Buddhism in particular, you'll benefit immensely.