In theory, the legal system is a logical and impartial process. In practice, there are many subtle factors, irrelevant to legal reasoning, that affect our decisions. These factors are: cognitive biases, emotional or social factors, and aspects related to the context and format in which the legal case is prepared and presented to the parties. The knowledge of these factors is fundamental to make law professionals more aware and alert of their presence, allowing the development of defenses against strategies of persuasion in which these factors are used in order to influence the decision process. In this training, we will present how certain psychological phenomena can be incorporated in different dimensions of legal argumentation, namely: 1) elaboration of legal pieces, including the part of the narration of the facts, the legal argument and the request, as well as the formatting and order of the text; and 2) factors that influence performance in court hearings. Beyond these, we will mention some behavioral strategies that may facilitate other aspects inherent to legal processes, particularly: 3) relationship with Justice officials; 4) negotiation and relationship with clients; and 5) management of legal deadlines.