This study explored the desired characteristics and behaviors of in-service trainers in the Schools of Foreign languages as viewed by EFL instructors at Turkish universities. The variables affecting the EFL instructors’ choices in relation to these desired characteristics and behaviors were also investigated. The study was conducted with 125 EFL instructors who were surveyed for their expectations and attitudes towards in-service trainers. The participants worked at the Schools of Foreign Languages at the following state universities: Kocaeli University (in the city of Kocaeli), Ankara University, Gazi University, and Middle East Technical University (METU), in the city of Ankara. Five of the participants were also interviewed to investigate their opinions about what variables affect their choices in relation to these desired characteristics and behaviors. The data were collected via a questionnaire and a semi-structured interview. The questionnaire had three parts. In the first part, questions related to the instructors’ personal information and professional background were asked. The other questions in the remaining two parts were directly related to the desired characteristics and behaviors of in-service trainers. In the second part, each question included a set of items to be rank ordered by the participants. In the third part, five-item Likert- scale questions were organized. In the semi-structured interview, three guiding questions were asked to the interviewees. The participants were also prompted to answer additional questions raised during the interviews. The results of the quantitative analysis revealed that the EFL instructors give more importance to the trainers’ communication and pedagogical skills rather than their higher academic degrees. The results also indicated that according to the instructors, a trainer should be able to provide practical knowledge to be used in the classrooms. In addition to these, the qualitative analysis revealed that previous experiences with in-service trainers, the conditions and circumstances at home institutions, the instructors’ own professional behaviors and characteristics, and the instructors’ previous experiences with their former professors in the BA programs were the factors which affected their choices in relation to the these desired characteristics and behaviors.