In order to gain insights into the voice profile in academic discourse, the present study investigated the realizations of voice in obligatory moves and steps in integrated Results and Discussion chapter of 40 master's theses from hard and soft sciences written by ESL students from 2002 to 2012. To conduct the study, a mixed-method approach was adopted. The quantitative analysis was conducted to locate the voices in the identified obligatory rhetorical units of the corpus. The shifts in the use of the voices and possible reasons for voice selection were investigated in the form of contextual analysis. It was found that the use of active voice outnumbered passive voice in the overall corpus. The disciplinary variations were observed mostly in Structure of the Section, Describing Aims and Purposes, Listing Procedures or Methodological Techniques, and Referring to Previous Research. The influencing factors in voice choice were the function of the step, the associated verb and tense, and the writers' stance in the text. [ABSTRACT FROM AUTHOR]