Historical research into teachers’ conceptions and practices is imperative when the goal is to make sound educational decisions. It is through these well thought out decisions that solutions can be conceived for current problems in the education system. The purpose of the study, outlined in the chapter, is to determine the conceptions of Portuguese history teachers concerning the subject they teach and how that affects their teaching in the classroom. The study also aims to find commonalities between the teachers’ conceptions and their personal and professional backgrounds. The chapter discusses the research method, population and results. The author concludes with a discussion of the results including some final questions that remain to be answered.