The main objective of this paper is to show that the syntactic behavior of negative polarity items (NPIs) allows us to assess whether or not an argument undergoes A-movement in Japanese. Japanese has two types of NPIs. One type of NPI, which is referred to as the 'argument modifier' type, is licensed with reference to the surface A-position of the argument which it modifies (i.e. this type of NPI is licensed in a position in which the argument appears after A-movement, if it applies) and the other, which is referred to as the 'floating modifier' type, can be licensed in the underlying theta-marking position where its host argument is first merged (i.e. the position before the host undergoes A-movement). Data regarding the two types of NPIs reveal that in Japanese, subject raising is conditioned by the property of tense (T): if T carries a Case feature to value the Case feature of a nominative argument, it also has an EPP feature to induce subject raising, but if T does not carry any Case feature, it does not have an EPP feature. The NPI data also show that in Japanese, negative nai is head-raised when it is associated with a predicate with some verbal properties.