This paper is an attempt to explore whether multipartism in Tanzania is conducive to the establishment of an effective parliamentary oversight regime. The underlying proposition is that if multipartism has impacted parliament positively then parliamentary oversight over public policy in various sectors has become more efficient and effective, leading to enhanced transparency and accountability in government. If, on the other hand, parliamentary debates on important questions have been focused on a narrower range of issues or where, indeed, some important policy issues have escaped parliamentary scrutiny due to some features of multipartism, then the document tries to establish the extent to which this could be the result of muzzling dissent in the narrow interest of party loyalty but at the expense of the greater national interest. The document looks at parliamentary oversight over the sensitive area of defense and national security.