This book explores cross-cultural and grade-based differences that exist within argument structures and various aspects of language features as constructed by undergraduate students in their argumentative/persuasive essays. It attempts to address a major complaint that academic staff voiced about tertiary student essays, concerning their lack of analytical, critical voice and formality in their arguments. The linguistic evidence for exploring these issues is based mainly on interpersonal systems of interaction, which draws on work dealing with the metaphorical realization of commands, and evaluation termed 'appraisal theory'. Appraisal theory is concerned with the linguistic inflection of subjective attitudes of writers (ATTITUDE) and also their scaling up and down of evaluation (GRADUATION) and intersubjective positioning (ENGAGEMENT). Both theories have been recently developed within a Systemic Functional Linguistics theoretical framework. This book also incorporates a social interactive model derived from 'Interaction in writing' alongside Bakhtin's dialogic literacy in order to emphasise a per-spective of writer and reader interaction. Under this broad interdisciplinary approach, this book demonstrates that a student's successful construction of academic argument can be examined from three main perspectives: Interactive (schematic structures), Interactional (the metaphorical realisation of commands), and InterPERSONAL (the three main appraisal systems).