The present paper argues that ECM subjects undergo A-movement to Spec of ForceP in the subordinate clause, but not to the matrix object position, in Japanese ECM constructions where a complementizer is required for the embedded clause. ECM subjects are argued to move to Spec of ForceP, accessible to the matrix predicate, while a topic fills the lower TopP. It is suggested that an ECM subject appears in ForceP on the grounds that it enters into f-feature agreement with the Force head, and that the Case feature of the ECM subject is valued as accusative by the matrix verb. It is further shown that when a major subject construction where both major subject and thematic subject are marked with nominative case is embedded under the ECM verb, the major subject rather than the thematic subject of the embedded predicate is raised to Spec of ForceP to serve as an ECM argument.