This article investigates the survey participation of migrants using data f
rom a quantitative survey of 759 Turkish respondents in Mannheim. Each phas
e of the survey (e.g. contact, cooperation) is analyzed separately in order
to identify the problematic subgroups in this population. The available fi
ndings about the process of migrants' survey participation show that female
, elderly, and poorly assimilated migrants can be expected to display rathe
r low participation rates. Based on these findings several aspects of the f
ieldwork were varied in an attempt to increase survey participation (e.g. t
he use of bilingual interviewers and questionnaires, gender homogeneous all
ocation of interviewers and respondents). The effect of these measures is a
nalyzed for several socio-demographic subgroups of the sample. We compare t
he survey participation of migrants to that of Germans as well as to that o
f other immigrant surveys. These analyses show that by using bilingual ques
tionnaires the only remaining underrepresented group is older migrants who
have high non-contact with Germans rates.