The Qatifi dialect of Arabic is spoken by a minority group located principally in Qatif, near Dhahran, in the eastern province of Saudi Arabia. Codeswitching in the Qatifi community describes the alternation, within discourse, between two local codes, such as switching from the Qatifi Arabic to either the Qatifi secret G, S, and T languages or to Classical and Modern Arabic, on the one hand. On the other hand, it describes the alternation between local and foreign codes, such as switching from the Qatifi Arabic to English, Farsi, and Broken Arabic pidgin.The Qatifi speakers frequently use the G, S, and T secret languages, which represent phonological variations in Qatifi Arabic according to particular rules. These secret languages are used by the Qatifi people to establish political solidarity, to secure social norms, or to insure discretion.Codeswitching from the Qatifi dialect to other local or foreign codes also affirms the social identity and personal pride of individuals taking part in informal conversation. It is important therefore to understand the social constraints of the society where it is found, and how it works within the linguistic rules of the source language and the mainstream communicative system. Codeswitching as spoken by the Qatifi middle class community identifies particular member of this minority group.The aim of this thesis is to explain codeswitching occurring between theQatifi dialect of Arabic and other language varieties. Using data drawn mainly from personal interviews with Qatifi natives, I investigate the type of code used in variable conversational settings and the interaction among the Qatifi trusted or non-suspicious members. / Department of English