The Work-flow View of Processes
Although there seems to be little agreement on what a process is or the main elements that make it up, the predominant view among academics and practitioners seems to be that a process is a set of interrelated activities (Hunt, 1996; Ould, 1995). In this sense, processes are seen as activity flows (a.k.a., work flows)composed of activities that bear some sort of relationship with each other (White and Fischer, 1994). This means that, if activities are not perceived as interrelated, they are not part of the same process.
Among activities in processes, there are at least three main types of relationships, which we refer to as: (a) common predecessor, (b) common successor, and (c) predecessor-successor. These relationships are illustrated in Figure 1.
1. "Receive Materials" Process of a Chimney
from Kock et al. (1997a, p.72)
In this figure, activities are shown within oval shapes, and the arrows indicate the flow of execution of the activities in the process. Also, a rectangular shape represents an external supplier of the process, whereas a diamond shape indicates a decision point in the process. Each activity is described by its name and followed (within parentheses) by the organizational function that carries out the activity and the italicized name of the main tool used by this function. Freestanding text that begins with a "dash" is used to describe a "product," which can be a piece of data or a material thing that flows between activities.
The common predecessor relationship joins together activities that have a common immediate predecessor activity. In the Figure 1 process, this relationship is shown by the activities order a replacement batch, which is carried out by the acquisitions assistant (usually by fax), and send a receipt to supplier, which is also carried out by the acquisitions assistant, who typically uses ordinary mail. Both activities have the same immediate predecessor - the inspect materials activity - that is done by the quality inspector, who uses specialized quality inspection equipment. This common predecessor must be carried out before each of these two interrelated activities.
The common successor relationship connects activities that have a common immediate successor activity. The activities stock materials and update stock system(the former done by the stock assistant with the use of a forklift and the latter by the sales assistant on a computerized stock system) are connected through a common successor relationship. Both activities have a common successor - the activity check materials in stock against stock system - which is performed by the production manager by walking through the stock warehouse and comparing it with the inventory database by using a laptop-based version of a computerized stock system.
The predecessor-successor relationship, the most common type of relationship between activities, joins together two activities that take place in sequence, one after the other. Note that, as with the two types of relationships described above, a predecessor-successor relationship can exist even if there is no flow of data or materials between activities. The activities receive tubes or parts and inform quality inspector of materials arrival are connected by a predecessor-successor relationship as they can only be carried out in sequence, the second after the first.
The process of creating work-flow representations of processes is typically called flowcharting. According to Harrington (1991, p. 86), this process is "... an invaluable tool for understanding the inner workings of, and relationships between, business processes." Irrespective of this opinion, however, work-flow representations of processes, such as those in Figure 1, illustrate an important point - although flowcharts can show the data or materials that flow between activities in a process, these data or materials do not actually flow between activities. Hence, the data-flow representation in flowcharts can be somewhat misleading. For example, the delivery form, which apparently flows between the activities inform quality inspector of materials arrival and inspect materials, in reality flows between the organizational functions that carry out these activities - acquisitions assistant and quality inspector. The delivery form is a data repository that allows for the exchange of information between these two functions. This shortcoming of the work-flow view can be of significant importance if the focus of a process redesign attempt is on the flow of data, not the activity configuration in a process. This is because the work-flow view "hides" information about the flow of data in organizational processes (Kock and McQueen, 1996).
There are a number of variations of work-flow representations similar to the one shown in Figure 1. The work flow in Figure 1 itself is an adaptation of the ANSI standard flowchart, and it has been extensively used in our work with process improvement groups. (See Kock (1995; 1999a) for a description of the use of this flowcharting tool in process improvement groups.) Flowchart variations include the block diagram, functional flowchart, functional timeline flowchart, and geographic flow-chart. (See Harrington (1991) for a more detailed discussion of these.)