This is the first new Thai-English dictionary by an American Scholar to appear in over twenty years. It includes many new words and new uses of old words that have entered the language since Wold War II, an it employs the latest official spellin of words (based on the Thai-Thai Government Dictionary of 1950), with some older spellings cross-referenced to the present spelling. Its 20,000 entries are presented in a sinle alphabetical listing: standard vocabulary items, names of people and organizations, place names, and abbreviatiions. The pronunciation of words is shown in a scientific writing which includes five tones, stress within rhythm groups, and intonation whenever clauses or sentences are cited. The pronunciation guide is not a translation; rather it is the standard pronunciation used by educated speakers in Bangkok, which often differs from the traditional spelling in tone and vowel length. Levels of usage-vulgar, common, colloquial, elegant, royal, and sacerdotal-are indicated whenever pertinent. Slang terms and idioms are included, and for words that American students find difficult there are grammatical comments and ample examples of usage.