Many manufacturing industries have made great gains by utilizing lean principles in the factory. These principles, which have perhaps been most successfully applied in the Toyota Production System, can be summarized as follows:

1. All work must be clearly defined as to content, sequence, timing, and outcome.
2. Every customer-supplier connection must be direct, explicit, and transparent, and an effective protocol must be used to communicate requests and information about deliveries and priorities.
3. The pathway for delivering every product and service must be simple, seamless, and well understood by the responsible agents.
4. Improvements to the above must be made through carefully controlled experiments, under the guidance of an experienced coach, at the lowest possible levels in the responsible groups.

Lean means the elimination of waste. In manufacturing, this typically means reduction of material in inventory, since that material is expensive, and since such reductions cause efficiencies in other important aspects, such as cycle time. In knowledge-based industries, waste is not extra people, as you might expect, but rather a reduction in the information and decisions that are 'in inventory', or essentially, in processing.  This waste reduction is usually further augmented with additional efficiency improvements, by balancing capacity against demand, and prioritizing work queues.

Lean practices have not yet made the penetration within engineering groups that they have achieved in manufacturing. I believe this is for several reasons. The first is that engineers don't always understand why cycle time is important to business; this article is a good summary of why competitiveness is so dependent upon this factor.

The second is the lack of a clear and brief explanation of how lean principles can be applied to the engineering environment. I believe this reason is effectively addressed by this presentation by Alistair Cockburn.

I believe that still another, even more pervasive reason for this lack of penetration is because there haven't yet been enough good examples and 'how-to' guidance available or shared on lean practices that have been relevant to engineering fields. As a result, many groups think lean practices are not relevant to what they do, or do not know what steps they might take to employ these techniques. The purpose of this article is to highlight examples where lean techniques have been applied succesfully within engineering groups, in the hope that such examples will motivate others to follow in these footsteps. Dive in, learn, and draw energy and motivation from these efforts: