<span class='abs_content'>This paper investigates the mechanism of argument movement in the derivation of grammatical Tiv construction. It examines Tiv as a syntactically ergative language and how ergative case is valued as well as the feature computation of T in ergative constructions. Raising constructions in Tiv is defined as hyper-raising and this paper also provides insight on how features in such constructions are valued so as to avoid a situation which this paper also identifies as feature roaming. The paper also considers the effects of phase heads: whether strong phase heads block movement or not; it also seeks to account for the features responsible for copy movement where it is operational in Tiv especially in subject to object...