Chan, Gloria Hong YeeGloria Hong YeeChanLo, Tit WingTit WingLoLee, G. K. W.2026-07-292026-07-292026https://repository.sfu.edu.hk/handle/sfu/5444The study of hidden, stigmatised, and digitally mediated populations poses a methodological challenge, as their social worlds are dispersed across public, semi-private, private, online, and offline spaces. Conventional ethnography, which is largely tied to specific physical sites, cannot fully capture these dispersed activities; nor can single-platform online methods explain how such populations move across interconnected platforms. This article develops a staged, ethics-attentive, multi-platform online ethnographic protocol, using the Hong Kong drug-related field as an illustrative case. The protocol begins with low-intrusion public mapping, moves to ethically managed engagement in semi-private spaces, and proceeds, where appropriate, to direct interactions, participant verification, informed consent, offline interviewing, and triangulation. It shows how hashtags, platform recommendations, symbolic codes, and cross-platform pathways can be treated as field signs rather than merely as recruitment tools. By implementing cross-platform data collection, the protocol also demonstrates operational strategies for ethical governance and data security that enhance the methodological robustness and credibility of the research. The article contributes by clarifying how online ethnography can be operationalised under conditions of hiddenness, traceability, legal sensitivity, and unstable online/offline boundaries. Rather than claiming universal applicability, the protocol offers a structured and ethically reflexive starting point that requires adaptation to different populations, platforms, legal contexts, and levels of ethical risk.enjournal article10.1177/16094069261473438