Migration research is an emerging field in the Czech Republic and data collection poses many methodological challenges. Some of the problems are universal for the research of other hard-to-reach populations. Other problems are, on the contrary, unique, applying only for the research of immigrants and could be country specific. This article focusses mainly on the quantitative research of immigrants where the issue of sampling problem is of major concern. The aim of the article is to address the issue of sampling immigrants in the context of the Czech Republic. In the first part of the article, there is a review of existing methodological approaches to researching immigrant populations. The focus here is on potential problems when applying particular methods in the Czech context. The second part of the article is dedicated to a review of four major Czech sample surveys of immigrants that are compared in terms of their methodology and basic results