This guide was prepared to facilitate the practitioner's selection of formal tests for evaluating communicative behavior in clinical infant populations during the first year of life. Clinical instruments with particular emphasis on communication and emerging language and speech abilities were identified in terms of publishers' recommended chronological age for test administration. Tests appropriate for children between birth and 12 months were further selected from the available database, reviewed, and summarized under eight different behaviorally defined categories. These categories concerned abilities in cognition, communication, expressive language, receptive language, gross motor skills, fine motor skills, personal/social skills, and "other," or miscellaneous, skills. Extensive tables display over 60 measures or tests by title, author(s), publisher, chronological ages tested, and main behavioral areas tested. An asterisk is placed beside behavioral categories assessed by each measure. (No value judgments were made about the quality of the tests reviewed.) (Author/RH)