The purpose of this research is to identify a core set of vocabulary used by native Urdu language (UL) speakers during dyadic conversation for social interaction and relationship building. This study was conducted in Karachi, Pakistan at an institution of higher education. This research seeks to distinguish between general (nonspecific communication) and social interactive communication used by UL speakers. The identification and establishment of high frequency word usage lists was utilized to construct and select core vocabulary for possible use in Augmentative Alternative Communication (AAC) tools and strategies. This descriptive study used observational methods to explore the reliability of transcribing Urdu language (UL) for utterance and word identification. The goal is to establish a core vocabulary list to support the development of AAC applications in UL. This cannot be accomplished until a systematic and reliable approach to analyzing conversational language samples in UL is demonstrated. Furthermore, the study replicated methods from similar previous studies in English by collecting and analyzing language samples from native UL speaking college students. The degree of similarity between the UL core and the English language core was also identified. A total of ten thousand three hundred and one (10,301) words were collected, during dyadic conversation of which nine hundred and seventy-six (976) were identified for a word frequency list. This list was compiled in hierarchical order based upon frequency of occurrences and percentage within the corpus. The results and analysis of the total corpus revealed the presence of nine (9) different grammatical categories including: 379 nouns, (38.8%); 246 verbs, (25.2%); 174 adjectives, (17.8%); 76 adverbs, (7.8%); 53 pronouns, (5.4%); 22 prepositions, (2.3%); 9 conjunctions, (0.9%); 8 interjections, (0.8%); 2 articles, (0.2%); and 7 other, (0.7%). A possible core of 100, 150 and 250 words were identified. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]