Every first-grade teacher is faced with the problem of teaching her pupils to recognize printed words as one of the first steps in the reading process. Each child must be led to recognize the visual symbol for each word and to associate it with the proper meaning. While many pupils find this a most difficult task, practically nothing is known concerning many of the factors conditioning the process. The present experiment was instituted to study factors which condition the acquiring of a reading vocabulary by first-grade chil dren, because during several preliminary investigations great varia bility had been found in the learning difficulty of the various words. Since this is essentially a classroom problem which every first-grade teacher must face, no attempt was made to conduct a laboratory experiment. Every effort was made to standardize the classroom procedure in the belief that if the difficulty were inherent in the word itself, it would become evident when the children's ability to recognize the word was tested. The children, fifty-six in number, were given the Binet test and paired as nearly as possible according to their chronological and mental ages. They were then placed in two rooms under teachers who were judged to be of similar ability and who had taught in the same school for a number of years. Textbooks adopted by the county were used, and the words studied were the first sixty in the text. The experiment was ex plained to the teachers and the following program of action was adopted: (1) Each new word was to be developed at a separate period, and three new words were to be taught each day for four days. Friday of each week was used for review and for testing. The teachers were not limited as to the method of teaching, but they were urged to teach each word so that it would make the deepest possible impression. In general, the effect was to cause the teachers to put more than the usual amount of emphasis upon word-recognition. This emphasis was evident during the reading 278