Harm to others research has a long association with advocacy for alcohol control. However, because current drug laws create harms specifically arising from the prohibition of markets, such research could also support drug policy reform advocacy. Wilkinson and Ritter's excellent paper on the alcohol harm to others (AHTO) paradigm raises some critical questions. It should stimulate much-needed debate on how approaches developed within alcohol research apply across other substances. The authors note that a primary motivation for the recent development of AHTO research was ‘to increase political will for enacting alcohol policy’ [1]. This places AHTO in a much longer lineage. Specifying and quantifying the social costs of drinking was a key strategy in the 19th and early 20th-century temperance movements [2, 3]. Then, as now, advocates understood that focussing on social harms, rather than only individual risks, could more effectively shift the political dial. The explicitly instrumental, policy-oriented purpose of AHTO research reflects the degree to that the alcohol research community has accepted the principle that research should serve the purposes of public health advocacy and support specific policy solutions [4, 5]. This is understandable in the context of enormously powerful and badly regulated ‘addiction industries’ [6]. Nevertheless, Wilkinson and Ritter rightly warn against this leading to biases in research, such as attribution errors arising from a lack of attention to wider social and psychological contexts. They could also have added that reporting proportions of respondents experiencing ‘one or more’ harms from a list that varies considerably in severity may, while producing more eye-catching headline numbers, imply all harms are equal [7]. The paper also notes that AHTO research, by necessity, side-lines the critical role that pleasure plays in individual drinking choices. This is not insignificant, even when the purpose of a study is specifically to quantify harm [8, 9]. How many respondents reporting issues like nuisance would also, given the opportunity, add that alcohol has more often been a source of pleasure? Highlighting the trade-offs and ambivalences that characterise attitudes to alcohol provides deeper sociological insights, but is liable not to feature in research designed to support stronger control policies. In focusing on the relationship between AHTO research and advocacy, this paper raises an important—as yet unanswered—question. Could, or should, AHTO research be used to advocate for drug policy reform? The harms of alcohol fall primarily on the side of consumption and the risk of increased consumption under lax regulation. By contrast, an enormous proportion of the harms to others currently associated with illegal drugs arise from the prohibition of supply: from the violence and exploitation endemic in the supply chain, to the adulteration of products and the widespread stigmatisation of even low-level use [10]. Starting where we are, it is hard to imagine that a body of research that considered ‘all harms inclusive of supply and consumption’ [1] would not, to some degree at least, strengthen the case against drug prohibition. The paper also highlights (both explicitly and implicitly) an unfortunate, but often unavoidable consequence of existing drug laws on the conceptual framing of substance use: the widespread tendency to divide psychoactive substances into alcohol on the one side and ‘drugs’ on the other. This misleading dichotomy is rooted entirely in social history and legal status, not effects, risk, chemistry or patterns of use [6, 11, 12]. Phrases such as ‘alcohol and drugs’ entrench this problem, and alternatives (such as ‘alcohol, tobacco and other drugs’) go only some way to resolving it. Although sociologically meaningful (insofar as it is a condition within which ‘drug cultures’ and consuming behaviours emerge) it is, in other respects, absurd that substances as different as, say, psilocybin and heroin are lumped together in the analysis of harm or the implementation of policy, whereas drugs with at least superficial parallels in use patterns and risk profiles (e.g. alcohol and cocaine) are dealt with separately [11]. This paper shows the real need for harm to (or from) others studies to be applied to illegal drugs, but also that such research needs to be granular. This would greatly improve our ability to comparatively assess the harms caused by illegality with those directly linked to use. It would help with modelling how the latter may increase, or decline, under a range of alternative regulatory systems: a vital question in addressing the future development of drug policy. Hopefully, this paper will create momentum toward such programmes of work. Transform Drug Policy Foundation receives donations from a range of trusts and foundations, including the Open Society Foundation, as well as individual donors. Transform does not accept funds from cannabis, tobacco, alcohol or pharmaceutical companies.