Answer:

Focus groups, interviews, conversations — These face-to-face techniques can be structured to provide very useful information; they may also allow for probing and follow-up to capture nuances very difficult to learn with a traditional survey.

In depth face to face interviews, even one on one telephone interviews, are among the most important tools or methods for conducting qualitative research. They're labor intensive and seem to be displaced somewhat by online and electronic approaches. But nothing really compares to the chance to interview a human subject in depth for maximizing the validity of your research. Questions such as, "What do you mean?" or "Can you give me a specific example?" have real power