Recent studies in contact linguistics have emphasized the aspect of language-internal grammaticalization that is triggered by accommodation to an external (contact-language) model (e.g. Heine and Kuteva, 2005). This is based on the notion that speakers make use of the available resources in order to match them to those of the target language. A problematic issue is contact-induced change in the domain of case representation. Synthetic case markers are usually thought of as fully grammaticalized morphemes. If contact-induced grammaticalization is, as Heine and Kuteva suggest, much like monolingual grammaticalization, unidirectional, how do we treat instances of rearrangement of the semantic meaning and scope of case markers? I will discuss this problem by examining a sample of Romani dialects, belonging to the so-called Northeastern dialect group (see Matras, 2002). Relying on specific constructions, like Subject of Negative Existence, External Possession, Privative, Partitive etc., I will compare and contrast the Northeastern dialects with their respective contact languages (Russian and Polish). Using semantic maps, I will demonstrate how the Romani dialects in question restructure their case representation system to accommodate to the systems of the model languages, and will discuss what it is exactly that gets equated when two languages come into contact.