Argentina’s national drug law, Law 23.737, has been in effect since 1989. Based on prohibitionist drug policy, this law was intended to severely punish drug traffickers and protect the public from drug use-related health concerns. However, it has failed to achieve these goals, and instead targets people who use drugs (PWUD) and brands them “criminals.” In response, the Argentine government announced its intent to reform Law 23.737 in 2008, sparking widespread debate among health, legal, and social service professionals. This article discusses this debate from the perspective of harm reductionists, those who work to reduce the negative effects of drug use rather than eliminate drug use or ensure abstinence. Drawing on archival research and 16 months of ethnographic fieldwork in Argentina, this article examines the positionality of harm reductionists in this drug policy reform, particularly the controversial proposal to decriminalize drug possession for personal use. Demonstrating their contention that Argentina’s legal apparatus is a major contributor to PWUD’s discrimination, stigmatization, and isolation from health and social services, I argue that challenging these problems through policy engagement allows Argentine harm reductionists to draw attention to the broader question of PWUD’s rights and to ultimately recast PWUD as rights-bearing citizens.