The accurate measurement of migrant remittances is central to understanding both the dynamics and the consequences of migration. Empirical studies rely on survey data about remittances, which are difficult to collect in a precise and reliable form. We explore the complexities and the challenges associated with the design of surveys on migrants‘ remittances, drawing upon our experiences over a number of studies in which we compiled and analysed data on migrants‘ remittances across a wide range of countries and contexts. Our goal is not to prescribe specific solutions, but rather to raise awareness of key methodological choices and their implications, not only among those engaged in survey design, but also among analysts who rely on data collected by others. We specify a number of definitional, methodological, and conceptual issues the researcher must address before embarking on the task of survey and questionnaire design. These include the need to take into account the various forms that remittances may take, the different channels through which they are transferred, the parties and relationships which could be involved, and the differences in the perspectives of senders and recipients, and of individuals and households. We also examine the implications of survey issues related to the sensitivity and the reliability of responses. Our results suggest that both survey designers and analysts who are relying on survey data collected by others should (1) be aware of the specific methodological choices involved in collecting survey data about remittances; and (2) set priorities that reflect (a) the substantive objective of the study, (b) the particular context at hand, and (c) the value of generating results comparable to those of surveys in other contexts.