What's the difference between PDCA and a Management System?

Last week somebody posted a survey on LinkedIn that asked whether "PDCA (-Plan-Do-Check-Act-) Approach can be referred [to] as [a] Management System." You can find it here. The last time I checked (a few hours before it closed) it had collected 381 votes, of which 78% said Yes and 19% said No.

But this is not a matter of opinion. It's a simple matter of fact, and the correct answer is No. What this means is that nearly 300 people who felt confident answering an Internet poll about management systems actually don't understand what a management system is. How is this possible?

To be clear, I recognize that this is a specialized area. And it's not like I think that if I know something, then everyone should know it. There are lots of topics I know nothing about. But neither do I answer Internet polls about quantum mechanics, or cellular biology, or derivative-pricing in hedge-funds.

I can't answer the question why four-fifths of the people who thought they knew the answer got it wrong. But at least I can explain why the other answer is right.

A management system is like a Constitution: it provides the framework for an organization's rules, and it defines roles and responsibilities. More exactly, a management system defines the processes that you use to do the work of your organization, together with all their interactions and controls. You define the interactions because nobody works in a vacuum: your organization's processes must somehow interrelate or interlock. And you define controls -- of some kind! -- to keep things from going off the rails. Defined roles and responsibilities can be (among other things) a kind of process control; KPIs are another kind. These are all the topics we've been discussing here over the last couple of months.

One way a management system differs from a Constitution is that it is more complete. The Constitution of the United States, for example, tells us how laws are made and enforced but doesn't tell us what the laws themselves actually say. A management system includes not only the framework of processes and authorities, but all the individual procedures and work instructions as well. Every wall poster reminding you to be careful of the risks from your machinery, every company-sponsored training class, and every calendar entry telling you it's time to recalibrate your gauges -- all these are parts of the management system too. 

So if you think of a management system as like a Constitution plus all the subsequent laws and stuff … you won't be too far wrong. Obviously most organizations are a lot smaller than most countries, so their management systems are far smaller and simpler than any country's body of legislation. But if you can think of your company as kind of like a small country, the idea is similar.

PDCA, by contrast, is just a generic model for how to do things -- pretty much anything, in fact. The letters stand for Plan-Do-Check-Act, and you can think of them as a simplified summary of the scientific method. Whatever it is you want to do, start by making a Plan based on what you already know (or think you know); then go Do it; then Check to see if you got the results you expected to get; and finally reAct based on whatever you learned in the "Check" phase -- either by revising your assumptions, updating your procedures, or concluding that everything is perfect and steaming full speed ahead. (Notice, by the way, that the PDCA model is truly generic, while a management system is specific to this or that organization in particular.)

When I say you can use PDCA for anything, I really do mean almost anything. One way or another, most of us use the PDCA model intuitively without thinking about it. Giving it a name just helps formalize the steps so that we can be systematic and intentional about them.

For example, let's say you want to camp out in the woods over summer vacation, and you decide to manage the trip according to the PDCA model:

• During the Plan phase you choose the campsite, decide how many nights to stay, and plan what to take.
• During the Do phase you buy your groceries, load the car, and go camping.
• The Check phase is when you talk about it on the drive home. On the one hand, the mosquitos were a real nuisance. On the other hand, camping next to the lake was great because you could go swimming every morning. And you all agree that next time you've just got to bring a lot more marshmallows to roast over the campfire!
• Finally, during the Act phase, you make some notes of the things you learned this year that you don't want to forget (bug spray, lake, marshmallows) and you paste them on next year's calendar where you will see them next summer.

So of course you can also use the PDCA model when you are implementing and maintaining a management system, in exactly the same way.  

• During the Plan phase you set up all your processes, document them, and appoint people to their respective roles and responsibilities. 
• During the Do phase you go do the regular daily work of your organization. 
• During the Check phase you inspect the results: this might mean looking at your KPIs, or at the results from internal process audits, or something else of the kind. And of course part of inspecting the results is comparing them with your targets. Are the KPIs red or green? Did the audit reveal nonconformities, or not?
• During the Act phase, you make management decisions based on the results you found during the Check phase. If all your KPIs are red, is something wrong with your processes? (Or conversely, if they are all green have you been setting the targets too low?) If the same nonconformities keep showing up in audit after audit, is there some systemic problem that you have yet to find and resolve?
• Then based on the management decisions you made in the Act phase, it's time to Plan for the next period (e.g., for the next year). What KPIs will you measure in this year? Where will you set the target that divides green from red? Also maybe you have had to redefine this or that procedure, based on the systemic problems you uncovered above. All of this goes into the Plan for the next year.
• And then it's time for the next Do phase, once again.
• And so on, over and over.

It's a good approach. It's systematic, and if you apply it right you should learn from your mistakes over time. If you are regularly learning from your mistakes, you should be making the organization better and better. So by all means apply the PDCA model wherever you think it can help you.

But it's just a model, or a method. It can never be a management system by itself.

Have I made the distinction clear? Leave me comments one way or the other.