Studying asylum adjudication in Switzerland, this article investigates how front-line practitioners in street-level organizations (SLOs) effectively exercise collective rulemaking power when they engage in construction of procedural rules, known as “asylum practice” rules. Asylum practice rules aim at standardizing decision-making by defining which profiles can be protected or not, according to each country of origin. These rules potentially influence individual discretion and refugee status determination by shaping which decisions street-level adjudicators perceive as possible according to asylum seekers’ motives, situation and country of origin. The article argues that, in the context of a judicialized asylum policy, the development of asylum practice rules is part of a strategic and adversarial game with the legal defense of refugees and the court reviewing asylum appeals to interpret asylum law and determine its specific applications.