The Gemba Walk is one of the most important tools managers have at their disposal to lead and manage effectively.
Gemba (現場?, which is also romanized as genba) is a Japanese term which means "the real place." Japanese detectives refer to the crime scene as gemba, while Japanese TV reporters or others who are reporting from a particular place might refer to themselves as reporting from genba (exchanging the M for an N).
In business, gemba, or genba, actually refers to the place within the business where value is created - either for the customer or for the business itself. For example, in manufacturing the genba refers to the factory floor, where the action is.
However, it can also be used loosely to denote, or point to, any "site" such as a construction site, sales floor or where the service provider interacts directly with the customer.
In lean manufacturing, the idea of gemba is that the problems are visible, and the best improvement ideas will come from going to the gemba, or the floor where the production is taking place. The gemba walk, much like Management By Walking Around (MBWA), is an activity that takes management to the front lines to look for waste and opportunities to practice gemba kaizen, or practical shopfloor improvement.
In quality management, gemba means the manufacturing floor and the idea is that if a problem occurs, the engineers must go there to understand the full impact of the problem, gathering data from all sources. Unlike focus groups and surveys, gemba visits are not scripted or bound by what one wants to ask.
Glenn Mazur introduced this term into Quality Function Deployment (QFD, a quality system for new products where manufacturing has not begun) to mean the customer's place of business or lifestyle. The idea is that to be customer-driven, one must go to the customer's gemba to understand his problems and opportunities, using all one's senses to gather and process data.
 Wickepedia - Gemba