A semi-structured interview is a method of research used most often in the social sciences. While a structured interview has a rigorous set of questions which does not allow one to divert, a semi-structured interview is open, allowing new ideas to be brought up during the interview as a result of what the interviewee says. The interviewer in a semi-structured interview generally has a framework of themes to be explored.
Semi-structured interviews are widely used in qualitative research;[1] for example in household research, such as couple interviews, this type of interview is the most common. A semi-structured interview involving for example two spouses can result in "the production of rich data, including observational data.