The interactions among demonstrative adjectives in certain genitive phrases and WH-words in Japanese are investigated in this report on a work in progress. It is argued that certain demonstrative adjectives in Japanese, such as "ano" ("that"), occupy the highest Spec position in DP and that they block A-bar movement out of DP; genitive phrases, such as "John-no" ("John's"), occupy the lower Spec position in DP. It is demonstrated by examples that demonstrative adjectives, irrespective of whether they are in the WH form or not, do not co-occur with other WH-words in DP, while genitive phrases can co-occur with WH-words. Findings suggested that the DP structure is similar to the clausal (or CP) structure in that the A-bar position appears higher than the A position, thus more articulated DP structures could be proposed. (Contains 10 references.) (NAV)