The principle of equality of arms is firmly entrenched in the jurisprudence of international tribunals, but hardly at all in domestic systems. This article argues for the principle to be applied in Botswana's adversarial system, as a way of ensuring procedural equality and enhancing fair trials. After examining the normative value of the principle, the article refers to a number of domestic jurisdictions that have applied the principle. It also examines the general acceptability of equality and fairness in Botswana case law. This represents a foundation for applying the principle in Botswana. The principle was developed by the European Court of Human Rights, creating its own concept of fairness in trials, irrespective of the position in domestic systems. Since the principle is of international origin, it is necessary to note that “judicial territoriality” and Botswana's dualist system do not pose obstacles to the application of the principle.