adding different lines including Line of Order Penetration which separates customer-induced activities from customer-independent activities Minimum expected wait times Potential bottlenecks and/or fail points Evolution The service blueprint has become one of the most useful tools in the services marketer's repertoire. Since its original development, a number of scholars have sought to increase its usefulness by adding various modifications that provide additional information and more demarcations. Zeithaml and Bitner recommend adding four lines to the map. (1) the Line of Visibility (as in the original); (2) the Line of Interaction which separates customer actions from service provider actions (3) the Line of Internal Interaction which separates the front office and the back office and (4) the Line of Implementation which separates management zone from the support zone. The addition of these lines helps to separate the functions of planning and controlling from support activities including preparation. Yet other scholars and practitioners have recommended adding different lines including (5) the Line of Order Penetration which separates customer-induced activities from customer-independent activities. Lovelock, Patterson, and Walker (2001) suggest that the service blueprint may also be useful for specifying the level of variation from standards that would be tolerated at each step of the process without affecting customers' perceptions of quality and timeliness. Zeithaml, Bitner and Gremler (2006) also recommended adding bottlenecks and fail points to the map. A bottleneck is a point in the system at which consumers waiting time is likely to exceed average or minimum tolerable expectations. A fail point is any point within the encounter that has potential to affect customer satisfaction or quality. These additions increase the diagnostic value of the service blueprint. Applications Service blueprinting has three main applications: simple representation; diagnosing operational deficiencies and service design (planning for structural change or new service development). (1) Simple Representation A basic application for blueprints is as a simple form of representing or codifying what is actually occurring in the current operation. In visual form, the blueprint can be used in training programs, employee manuals to help clarify service processes. Blueprints may be used in market research as a means of helping respondents to visualise aspects of a service that may be the focus of an investigation. Blueprints can also be used in employee training programs and manuals to assist staff to visualise the service process and the relationships between steps in the process. (2) Diagnosing Operational Deficiencies Blueprints