Internet surveys are the future of migration studies given that migrants engage more and more often in multidirectional movements and reside in multiple destination countries. The richness of the growing variety of geographical and temporal migrant trajectories pose particular challenges for quantitative researchers studying such spatially dispersed populations for which sampling frames are not available. The Web-based Respondent Driven Sampling (RDS) method addresses many of the challenges occurring in such a context. However, its implementation is not an easy task and does not succeed in all migratory settings. The goal of this chapter is to outline the opportunities and challenges associated with using Web-based RDS for researching migrant populations. While the RDS method can be powerful in fact-to-face interviews, its usefulness in Internet surveys is debatable. We examine this issue by using the example of a survey of Polish multiple migrants worldwide conducted in 2018–2019. We outline observations from the fieldwork (selection of seeds, formation of referral chains, etc.), and discuss the challenges of using Web-based RDS by focusing on the barriers to referral chain formation related to RDS assumptions and study design. The observed constraints relate to the definition of a target group, the management of incentives online, and the anonymity issues of online surveys.