Of the many tools user experience researchers use, contextual inquiry is often one of the least known. Despite this, it's a great way to uncover usability issues. When it comes to finding inefficiencies in tasks or workflows resulting from bad design, contextual inquiry should be one of the first methodologies you try.
So, what is contextual inquiry?
Contextual inquiry is reminiscent of anthropological research, and relies heavily on participant observation. For this reason, it's a highly qualitative methodology that does not require a big sample.