In Romania, as elsewhere, there is persistent controversy surrounding homeopathy wherein various parties try to draw the boundaries of legitimate medical practice. The literature on complementary and alternative medicine features little discussion on the temporal dimensions of controversies surrounding these therapies, focusing mainly on the temporalities of the lived experience of treatment. Yet time is a powerful resource for challenging and gaining legitimacy. In order to capture the use of time as a resource for legitimating or contesting homeopathy, we advance the theory of time work by examining the rhetorical role of different temporalities in this dispute. We find that proponents and users of homeopathy appeal to temporal properties of treatment, such as the longer duration of consultation, and of healing, namely, a specific sequence of symptoms and reactions, stories of failed biomedical treatments followed by successful homeopathic interventions, and stories of durable efficacy. Critics invoke the temporal properties of science, especially a cumulative record of failed attempts to prove homeopathic efficacy beyond placebo, or to causally account for its putative effects. Argumentative time work also involves manipulation of temporal modalities, in which homeopathy is legitimized both through continuity with the past and through breaking away from the past, with an eye to a promised future. At the same time, critics of homeopathy invoke temporal modalities to cast homeopathy as a relic of an unscientific past. This research illustrates the value of "argumentative time work" as a conceptual tool in examining public controversies.