A qualitative data collection method used in media and market research where an interviewer and research participant have a semi-structured one-on-one discussion (often with the use of an interviewer guide) to gather rich and detailed descriptive data about behaviors (see “Behavior”), attitudes (see “Attitude”) and perceptions of a topic of interest. The structure allows both the interviewer and research participant the ability to probe deeper into certain points, explore additional areas and/or change the direction of the conversation if necessary. Also referred to as “Interview, Depth” or “Interview, Qualitative.”