The purpose of this study was to investigate whether task focused external/private speech could improve the performance of subsequent inner-speech, for mental arithmetic style problems. In addition, the role-played by task focused external/private speech as a meta-cognitive tool, was examined. It has been observed that external/private speech can improve participant performance on some verbally based problem solving tasks, (Duncan 2000). Moreover, it has been observed that the phonological loop, which in general terms is driven by inner-speech, plays a central part in mathematical multiplication tasks, (Seitz and Schumann-Hengstler 2000). Salame & Baddeley (1982) stated that arbitrary internal speech, such as repeating the word "the" inhibits various interference effects, by completely engaging the phonological loop. Therefore, this study suggested that task focused external speech may serve a similar function. Furthermore, the study proposed that subsequent internal task focused speech might as a result of the external practice emulate various meta-cognitive properties associated with external/private speech. The first hypoFinal Year Project for the study was that participants undergoing the mental arithmetic task in an external/private speech condition, would perform significantly better than participants attempting the task in the silent condition. The second hypoFinal Year Project for the study, was that participants in a previously practiced private or external speech, experimental condition would achieve superior performance on a subsequent inner speech based multiplication task, than participants in a control condition who practiced without using external/private speech. These hypotheses were tested using a repeated measure between subjects design, where participants were split into an internal and external condition for solving mathematical calculations. After performing fifteen multiplication tasks both groups were instructed to perform the same fifteen multiplications internally. Both hypoFinal Year Projectes were supported by the data obtained from unrelated t-tests. The discussion related the findings of the study to the debate concerning the relationship between language and thought, and the prospect of a possible curvilinear relationship between speech and thought. Future research and practical applications were also discussed.