The monograph describes the development of verbal behavior over a 20-year period in two deaf Japanese children (5- and 7-years-old when first contacted by the author) with whom previous training attempts had failed. It is noted that prior training methods which had succeeded with Laura Bridgman and Helen Keller failed with these two children. A detailed analysis of the problem is given which results in differentiating between aboriginal signs (purely instinctual) and constructive signs (the conscious forming of particular communicative patterns), subdividing constructive signs into symbolic signs and pattern discriminative signs, and further subdividing pattern into discriminative signs gestalt-qualitative signs and synthetic signs (the ordering of phonemes or alphabetical units). It is explained that the analysis led to the establishment of the following training program policies: the acquisition of the synthetic sign system as the primary goal and Japanese Braille as the first synthetic sign system to be learned. Explained is the use of the matching technique as the primary training method with rewards given for successful performance. A chart details the training steps leading to the acquisition of Braille from steps in learning to match on the basis of shape to steps in learning to match objects with their names in Braille. Also detailed are steps in the acquisition of the vibration method of producing vocal signs from controlling lip formation to integrating lip formation, breathing, and throat tension. Stressed is the role of a synthetic sign system in the organization of behavior for the deaf blind. (DB)