This article addresses some issues concerning the interactions between Neg and Tense in Japanese: (i) Does aru-support (= be-support) exist?; (ii) does susupport (= do-support) exist in tensed negative sentences?; and (iii) does Neg-to-T movement exist? It is pointed out that none of these questions can be answered in an affirmative way and proposed that all the relevant properties on Neg and Tense in Japanese fall out from a simple fact: Neg in English and its counterpart in Japanese possess morphologically different properties, although both of them are syntactically independent lexical items taken from the lexicon. Some implications of the proposal to the grammar of Japanese and UG are also briefly discussed.