Value Stream Mapping and Beyond

Overview

Value Stream Mapping (VSM) is a LEAN technique, used to map out process steps in order to both illustrate and understand:
•where work is occurring
•where delays or waste is occurring
•how much work of different types are in the system.

A Value Stream Map also identifies queues, wait times, waste, cycle times and other useful pieces of data. A Value Stream Map helps design visual representations of the work (e.g. Kanban Boards on the walls) and provides candidates for targeted improvement efforts.

What is a Value Stream?

A Value Stream identifies all the steps needed in order to make and deliver a specific product. In redesigning a Value Stream, the ideal result is a continuous smooth flow of valuable new features into production with no delays or waste anywhere in the stream.

The value stream is not just the development process, it includes everybody from the customer to operations and support engineers, and may even include marketing, sales and any other Business Unit that impacts on the stream of work.

Criticisms

The word stream implies that the work passes through a smooth, unbroken, and defined sequence of steps. The reality in a Complex Adaptive System may be quite different:

•When building a software product, specialised steps may be required for some parts of the system, but not others.
•For complicated products it is common for paths to change, and it may be rare for any two software modules to follow exactly the same path.
•In a system that is undergoing continuous change (due to retrospectives or other improvement processes) any process map may be outdated before it is completed.
Defining the workflow too precisely may lead to a rigid, unvarying process being applied where a looser, flexible approach may be more appropriate in order to allow for emergent and changing needs.

However, defining the workflow too loosely may reduce the value of mapping the process. The correct balance will depend on the intended purpose of the mapping.

If the system does not seem to be mappable as a stream of value that follows a defined sequence of steps, then Process Mapping may be more valuable (see below).

When is VSM Useful?

Use VSM:
•When looking for waste, or for areas that offer opportunities for process improvement. (Ask how much work went into this step, and how much value came out?)
•When you need to track one isolated flow in a complex series of chains (particularly if you want to experiment with a process change in one isolated area, with a limited, mapped and understood scope for impact).
•When the process can be mapped as a relatively simple chain of events.
If the process can't be mapped as a relatively simple chain of events then Value Stream Mapping may not be the ideal tool (see below for criticism and alternatives).

How To Run A VSM Session

To prepare a Value Stream Map:

1. Make sure the process is facilitated by an expert with a strong understanding of value stream maps.
2. Get feedback from at least one representative from all of the areas within the value stream being mapped.
3. Do not have your facilitator take notes and then prepare the map in isolation - involve the full team and create the initial Value Stream Map collaboratively
4. Create your initial value stream map using a pencil (you will need to make frequent corrections and changes) on a sheet of butcher's paper. 
5. Once you have the initial map, you can create an electronic version using Visio, or a similar tool..

Make sure you note the metrics needed to detect waste. For example, if you are seeking to improve cycle time, then for each step in the process note down how long the item spent at that station and how long it actually took to be processed. For example, it is common to find that a manager exists as a "gate" in a process - required to make a go/no go decision. Although the manager may be able to make the decision in a few minutes, most managers are busy, and may take days to get to the decision. So although the processing time was only a few minutes, the time at the station was days. Moving the decision to a lower level may make a dramatic difference to the total cycle time.

Once you have mapped the process and eliminated waste, your goal should be to further improve the process. Ask (from a customer perspective):

•What would the ideal flow of new features look like from a customer perspective?
•To make this happen, what would need to happen and in what order?
•What resources would need to be available to make that possible?
•How would roles and responsibilities need to be defined?
•What is the ideal flow?
•What is the best flow we can achieve?
•How can we improve to meet the ideal?
 These questions may suggest possible areas of improvement.

Note: Visio supports Value Stream Mapping shapes. You can find them in Business->Business Process->Value Stream Map Shapes.

An Alternative - Process Mapping

If the system is complex and the path is variable, then it may not be possible to map the process as a simple sequence of steps. In that case, use an alternative to Value Stream Maps, such as Process Mapping.

 Process Mapping is from the Systems Thinking side of Agile and is closely aligned with the Vantage method - so is very focussed on the point at which the customer interacts with the system.

In Process Mapping:

•Don’t ask the managers - they may know the ideal process, but they are often too removed from the work to know the special cases, alternate paths, or even perhaps the actual process.
•Don’t just send in a Business Analyst to talk to people - people are busy, and may even be wary of revealing the full horror of the process.
•Don’t talk to proxy customers or talk to a spokesperson for an area because, once again, you will only learn the ideal process.
•Don’t try to map the process in a room with butchers paper and sticky notes, bringing people in as required.
•Instead go into where the work is occurring, with a small team comprised mostly of peers of those who do the work.

Why peers? Because workers tend to tell their colleagues the truth about what’s really going on at work.

Study the work as a series of systems, viewed from the customer's point of view. Start at the point at which the customer first contacts the system and work out from there.

 Map the system as a series of varying interactions between subsystems. Define the customer's needs and document the sub-system interactions from the customer's viewpoint - explaining how each sub-system contributes to those needs. To improve the system, ask how could the work (mapped as a path through subsystems) be redesigned to support the customer's varying needs. How could the sub-systems be redesigned? How could the interactions be redesigned?

When is a Process Map Useful?

If you have one or more of these problems:
•Multiple entry points to processes
•Independent but interacting processes
•Workflow path is extremely variable, with few or no steps guaranteed
then a Process Map may be of use - either in addition to or instead of, a series of Value Stream Maps:

For more on Process Maps: http://nnphi.org/CMSuploads/MI-ProcessMappingOverview.pdf.