This paper investigates the treatment of Japanese speech levels and styles (known as "keigo") in previous studies and discusses the problems involved. An attempt is made to reconstruct the classification of speech levels and styles in modern colloquial Japanese. Speech styles change according to age, social status, sex, and the relationship of the speakers. "Keigo" may be classified into three types: the exalted, the humble, and the polite. The writings of several linguists on "keigo" are summarized, and they reveal a controversy over treatment of polite or elegant words. The following reconstruction of speech classifications is suggested: Speech consists of two components: level and style. Level has subdivisions of honorific and neutral, while the honorific level is further classified into exalted, humble, and polite. The exalted is used to show a speaker's respect for the action or state of a person in higher status. The humble shows humility with respect to the action or state of the speaker or listener. The polite shows a speaker's decision to speak politely or carefully through his expression on the topic. Each level is further modified by informal or formal style, conveying directly the speaker's evaluation of the listener. (CHK)