Using an Ethnographic Method to Gather Usability Data from the Field
http://www.stc.org/ConfProceed/1996/PDFs/Pg294299.pdf

Carlevato, Denise
STC Proceedings
1996

Abstract:

Observation is a way to gather rich information about how users work with software products that also provides a clearer understanding of the users' work. The method consists of watching users performing their normal work routine where they work. Observers can be usability professionals or trained individuals from the company. The richness and type of data collected can be used to identify design opportunities for the next release, define usability goals for all products, and create realistic customer scenarios.