Nova: Picture this. A Fortune 50 company installs a multimillion-dollar enterprise software suite. They've got the best hardware money can buy. Consultants are everywhere. And yet, eighteen months later, nothing has improved. Sales haven't gone up. Costs haven't come down. And the CEO is asking what went wrong. Today we're diving into a book that answers that question before you even spend the first dollar: ERP: Making It Happen by Thomas F. Wallace and Michael H. Kremzar.

Nova: : And here's what grabbed me right away, Nova. The book opens with something that feels almost confrontational. The authors write, and I'm quoting: "This is not a book about software. One more time: This is not a book about software." That's a pretty bold statement for a book with ERP in the title.

Nova: It really is. And that deliberate provocation is the key to the entire book. Wallace and Kremzar argue that the world has gotten ERP completely wrong. ERP is not the software you buy. It's the set of business processes, the decision-making framework, the way your people coordinate across departments. And Thomas Wallace was uniquely qualified to make this case. He was a pioneer in Sales and Operations Planning, a Distinguished Fellow at Ohio State, and someone who consulted for Boeing, Microsoft, Honda, and Procter and Gamble. He wrote twelve books before passing away in 2021 at age 85.

Nova: : So this isn't a tech manual pretending to be a business book. This is a battle-tested methodology from someone who spent decades in the trenches.

Nova: Exactly. And the stakes are enormous. The authors cite companies that increased sales by 20 percent during an industry-wide decline, simply because they could out-deliver their competition. Others achieved cost savings in the billions. But here's the thing: those wins didn't come from installing software. They came from changing how people work. So let's unpack what that actually means.

Nova: So let's start with the core idea that Wallace and Kremzar hammer home relentlessly: ERP is not software. They actually say it twice on the very first page, as if they're worried the reader won't believe them the first time. They even invented a separate acronym, ES, which stands for Enterprise Software, to distinguish the technology from the actual practice of Enterprise Resource Planning.

Nova: : I have to admit, I was skeptical when I first heard that. I mean, everyone talks about buying an ERP system. SAP, Oracle, Microsoft Dynamics. Those are ERPs, right?

Nova: That's exactly the sloppy terminology Wallace and Kremzar called out back in 2001, and they were writing in response to the Y2K era when companies were throwing millions at software installations. Their argument is nuanced. Yes, enterprise software packages contain some ERP functions like master scheduling, MRP, and capacity planning. But many ERP processes like Sales and Operations Planning and performance metrics exist outside typical software suites. And many things inside those software suites, like accounts receivable, general ledger, and human resources, aren't really ERP at all.

Nova: : They mapped this visually in the book with a Venn diagram showing three categories: ERP processes not in typical software, ERP processes found in typical software, and non-ERP processes found in the software. It's like saying not everything inside the box labeled "ERP software" is actually ERP.

Nova: Right. And the analogy they used is brilliant. They said ERP software is like a set of golf clubs. You could give the most expensive clubs ever made to one of the authors and he wouldn't break 120. Why? Because he doesn't know how to play golf. Meanwhile, if you send Tiger Woods out with just a four-wood and a sand wedge, he won't win any tournaments either. You need both: the skills and the tools. Too many companies bought the expensive clubs and never learned to swing.

Nova: : That hits uncomfortably close to home. The business press is full of ERP failure stories, but Wallace basically says those aren't ERP failures at all. ERP wasn't even attempted. It's like saying golf failed because you bought expensive clubs and still stink at golf.

Nova: Precisely. And this reframing leads to the book's definition of ERP: an enterprise-wide set of management tools that balances demand and supply, links customers and suppliers into a complete supply chain, employs proven business processes for decision-making, and integrates across sales, marketing, manufacturing, logistics, purchasing, finance, product development, and human resources. The goal is high customer service, high productivity, lower costs, lower inventories, and a foundation for effective e-commerce.

Nova: : Let me ask the obvious question then. If ERP isn't about the software, what is the implementation actually about?

Nova: Wallace and Kremzar lay out something called the ABCs of Implementation, and it flips most people's assumptions upside down. Item C, the least significant element, is the computer, both hardware and software. It's essential but lowest priority. Item B is the data, the inventory records, bills of material, routings. More significant. And Item A, the most important element by far, is the people. If the people understand the objectives and how to get there, they'll take care of the data. They won't let the computer tail wag the company dog. People are the key.

Nova: : So the book is essentially saying that the entire ERP industry has been misnamed and misdirected for decades. That's a pretty radical position.

Nova: It is. And Wallace was uniquely positioned to make it. He was the editor of the fourth, fifth, and sixth editions of the APICS Dictionary, which is the definitive terminology guide for operations management. He literally wrote the definitions that the profession uses. When he told people ERP isn't software, he was speaking from a position of genuine authority.

Nova: : And this came from real results, not theory. The book is co-authored with Michael Kremzar from Procter and Gamble, who was directly involved in P&G's rollout across North America, Europe, Latin America, and Asia.

Nova: Yes. And that brings us to the implementation methodology itself. Wallace and Kremzar didn't just diagnose the problem. They provided what they called the Proven Path. Let's get into that.

Nova: Wallace and Kremzar open their chapter on the implementation challenge with something they call Catch-22. And it's a brilliant diagnosis. Here's the trap: first, implementing ERP is a lot of work. Second, it's a do-it-yourself project. You cannot subcontract it to consultants. And third, it's not priority number one because the people who need to do it are already busy running the business.

Nova: : Wait, let me make sure I understand that second point. The book says you can't hire consultants to do the implementation for you?

Nova: Consultants have a real role in providing expertise and guidance, but the fundamental principle is Implementers equals Users. The people who implement the tools need to be the same people who will operate them. Only company people know the business well enough and have the authority to change how things are done. When implementation responsibility is separated from operational responsibility, nobody is accountable. The implementers can blame the users, and the users can blame the implementers.

Nova: : That actually makes a lot of sense. If I hire someone to reorganize my kitchen, they might set it up in a way that makes sense on paper but doesn't work for how I actually cook. Same principle.

Nova: Exactly that. And this leads to a fundamental tension. Running the business is always priority number one. You can't stop shipping orders to work on ERP. So Wallace recommends ERP be pegged as the number two priority, right below running the business. Not number five, not something we'll get to when things slow down. Number two. And this is where the Proven Path comes in.

Nova: : Alright, what exactly is the Proven Path?

Nova: The Proven Path is a well-defined set of steps that Wallace and Kremzar say guarantees success if followed faithfully. It's not theory. It emerged from observing thousands of companies over 35 years, watching what worked and what didn't. The methods that failed got discarded. What worked got refined and synthesized. The Proven Path has been battle-tested by companies like Boeing, Honda, Pfizer, and countless others.

Nova: : So there's actual empirical evidence behind it, not just consulting-speak.

Nova: Absolutely. And one of the most practical elements is the concept of the Three Knobs. In project management, there are three variables: the amount of work to be done, the amount of time available, and the amount of resources available. You can hold any two constant by varying the third. For a company-wide implementation, Wallace recommends an aggressive 18-month schedule. The work is fixed. The time is fixed at about a year and a half. That means the resource knob is the variable. You have to put enough people on it.

Nova: : But what if a company genuinely can't allocate more resources? Not everyone has Boeing's budget.

Nova: That's where the book gets really clever. Wallace and Kremzar introduce something called Quick-Slice ERP. With Quick-Slice, resources are considered constant because they're limited. Time is fixed at a very short, aggressive three to five months. So the variable becomes the amount of work. Instead of implementing ERP across the entire company, you pick one or several high-impact product lines using Pareto's law. You focus on the vital few products that generate most of your revenue.

Nova: : So it's like saying: don't try to boil the ocean. Pick the 20 percent of your products that drive 80 percent of your business and implement ERP just for those first.

Nova: Precisely. Get a win fast. Build momentum. Then do another Quick-Slice, or expand to company-wide. Wallace and Kremzar also stress that if a given business unit takes longer than two years, the odds of success drop sharply. The intensity fades. Enthusiasm wanes. The world changes. People get promoted or leave. An aggressive schedule isn't just desirable, it's necessary.

Nova: : There's something almost counterintuitive in what they claim about aggressive schedules. They say tight schedules are actually less likely to slip than loose, casual ones. Why is that?

Nova: Because urgency focuses attention. When people know the deadline is real and close, they make different decisions about what gets their time. A project with a vague three-year timeline gets pushed aside whenever the business gets busy. A project with an 18-month deadline has a different kind of gravity.

Nova: : And the lost-opportunity cost is staggering. The book says that for many companies, a one-month delay can exceed a hundred thousand dollars in deferred benefits. A year's delay can run into the millions.

Nova: One of the most enduring frameworks from Wallace and Kremzar's book is the ABCD classification system. It was originally developed by Oliver Wight, the pioneer whom Wallace credits with developing most of the resource planning concepts still in use today. And it's brilliantly simple.

Nova: : I love a good classification system. Walk me through it.

Nova: Class D is the lowest level. Information is inaccurate and poorly understood by users. The system provides little help in running the business. Wallace makes a pointed observation here. People often call Class D installations a computer failure, but he says that's a bum rap for the computer. The computer is the only element doing its job. It's working fine. What failed is the people. They failed to implement and operate the tools successfully.

Nova: : That's harsh but fair. What about Class C?

Nova: Class C means a company has reduced inventories, sometimes substantially, and is better at managing engineering changes. The return on investment is actually pretty good. But the company hasn't really changed how it runs the business. It's using ERP primarily as a better way to order materials. Wallace calls this the stage where many companies get stuck and decide it's good enough.

Nova: : So Class C is where you get some benefit but nowhere near the full potential.

Nova: Right. Class B is where things get transformative. The company has dramatically improved on-time delivery to customers, minimized shortages in the plant, avoided unplanned overtime, reduced inventories, and can cope with the constant changes that hit a manufacturing organization. And then Class A is the top. The entire business is managed with one consistent set of numbers, from top management's sales and operations plans all the way down to detailed schedules for the plant floor and suppliers. Financial plans are developed from the same operational numbers used day to day. Extensive what-if simulation is possible in both units and dollars.

Nova: : And the book is designed to get companies to Class A.

Nova: Yes. And one of the most critical elements for getting there is something Wallace dedicated his entire career to: Sales and Operations Planning, or S&OP. The authors identify S&OP as the most important early win in any implementation. It's a powerful process to balance demand and supply at the volume level, giving top management far greater control over operational aspects of the business.

Nova: : Wallace was known for a particular phrase about S&OP, right? Something about a moose?

Nova: Yes. He famously said, "Good S&OP puts the moose on the table." It's a colorful way of saying that S&OP brings key planning challenges to the surface where they can be addressed quickly. Instead of hiding problems, you make them visible and deal with them. He also said, tellingly, "It's not balancing demand with supply, but it's balancing supply with demand," highlighting that markets had become demand-driven, not supply-driven.

Nova: : That shift in wording is subtle but profound. Balancing supply with demand means the forecast drives everything, not the other way around.

Nova: Exactly. Wallace wrote what's still considered the seminal handbook on S&OP, published in 1999, and his approach was forged in the 1970s when supply chains were going global, consumer behavior was shifting, and demand variability was increasing. His ideas have streamlined operations for thousands of companies. The savings from his work are, as one tribute put it, "so vast as to be unquantifiable."

Nova: : So in the book's framework, S&OP sits alongside other critical implementation steps: Project Launch, Initial Education, Process Definition, Data Integrity, and then Going on the Air in phases. Can you highlight some of the less obvious ones?

Nova: Data Integrity gets an entire chapter, which is unusual in business books. Wallace and Kremzar argue that without accurate inventory records, accurate bills of material, and accurate routings, everything else collapses. They also emphasize Initial Education, not just training. Education is understanding concepts. Training is applying them day to day. You need both. And they're explicit that untrained users may need three to six times as much support as properly trained users.

Nova: : It sounds like Wallace sees this as fundamentally an education and change management challenge dressed up as an operations problem.

Nova: That might be the single best summary of the book I've heard. Wallace and Kremzar say experienced users told them implementing ERP was harder than building a new plant, introducing a new product, or entering a whole new market. It requires massive behavioral change. But then they drop the most confidence-inspiring line in the entire book: ERP has never failed to work, not once, when correctly implemented.

Nova: Wallace and Kremzar trace the evolution of ERP through four distinct stages, and understanding this history is crucial because it explains why ERP looks the way it does today. It all started in the 1960s with Material Requirements Planning, or MRP.

Nova: : What was MRP trying to solve exactly?

Nova: It was born from early efforts in bill of material processing. People were looking for a better method of ordering materials and components, and MRP was the answer. Wallace boils it down to what he calls the universal manufacturing equation. Four questions: What are we going to make? What does it take to make it? What do we have? And what do we have to get?

Nova: : That's remarkably elegant. And the answer comes from three inputs: the master schedule tells you what you're making, the bill of material tells you what it takes, and inventory records tell you what you already have.

Nova: Exactly. But here's where it gets interesting. Early users quickly discovered MRP could do something far more powerful than just ordering. It could detect when the due date of an order was out of sync with its need date. For the first time ever in manufacturing, there was a formal mechanism for keeping priorities valid in a constantly changing environment.

Nova: : Because change is the only constant in manufacturing, right?

Nova: Wallace says change is not just a possibility or a probability. It's a certainty. The only sure thing. But priorities are only half the battle. The other half is capacity. Do you have enough? So the next evolution was Closed-Loop MRP, which added capacity planning tools, master scheduling, demand management, and feedback mechanisms from execution back to planning so plans could be adjusted when necessary.

Nova: : And then came MRP II, Manufacturing Resource Planning, which Wallace describes as the direct predecessor to modern ERP.

Nova: MRP II added three critical elements: Sales and Operations Planning, which we discussed; a financial interface that translates operating plans in physical units into dollars; and simulation, the ability to ask what-if questions and get actionable answers. Wallace and Kremzar use the APICS dictionary definition, which Wallace himself edited, that calls MRP II "a method for the effective planning of all resources of a manufacturing company."

Nova: : And then ERP, the fourth stage?

Nova: ERP takes all of MRP II's capabilities and broadens the scope. It applies resource planning tools across the entire enterprise, not just manufacturing. It provides real-time integration of sales, operating, and financial data. And it connects resource planning to the extended supply chain of customers and suppliers. The fundamentals are the same, but the reach is much wider.

Nova: : One thing that struck me is how universal Wallace claims ERP is. He lists nearly twenty different types of manufacturing environments and says ERP has been successfully implemented in all of them. Make-to-stock, make-to-order, design-to-order, process manufacturing, job shop, flow shop, single plant, multiple plants. He compares ERP to Generally Accepted Accounting Principles.

Nova: That comparison is really powerful. Wallace says people sometimes say, "We're different, we're unique, ERP won't work for us." And he responds: we've heard that for years. But nobody says, "We're different, we're unique, GAAP won't work for us." ERP is the logistics analog of GAAP. It's a defined body of knowledge containing the standard best practices for managing that part of the business.

Nova: : The difference being GAAP has been around for four centuries and ERP for about four decades.

Nova: Right. Wallace also makes a compelling case that ERP is the foundational layer upon which other improvement initiatives depend. Lean Manufacturing, Six Sigma, Employee Involvement, all of these are excellent tools with enormous potential. But none of them will yield their full potential unless they're coupled with effective forecasting, planning, and scheduling.

Nova: : He has a great line about that: "It's not good enough to be extremely efficient if you're making the wrong stuff. It's not good enough to make items at a very high level of quality if they're not the ones needed."

Nova: That's exactly the point. And it's worth noting that Wallace didn't see ERP as competing with Lean or Six Sigma. He saw them as complementary. A colleague of his, Chris Gray, articulated it beautifully: business process improvements take one of three forms. Improving process reliability is where Six Sigma lives. Reducing process complexity is where Lean Manufacturing lives. And coordinating the individual elements of the overall set of business processes is where ERP lives. You need all three.

Nova: Wallace and Kremzar are remarkably honest about a scenario they call the dilemma company. These are organizations that are already in the middle of installing enterprise software or about to begin, and the software installation is the priority. The problem is simple: installing enterprise software is an enormous task. It consumes huge amounts of people's time. If those same people are supposed to implement ERP processes simultaneously, they simply don't have the bandwidth.

Nova: : This sounds like most companies I've encountered. They buy the software first and then hope the process improvements will follow.

Nova: Exactly. Wallace's advice for dilemma companies is refreshingly pragmatic. He says: don't try to implement ERP simultaneously with installing enterprise software if you know your people don't have the time. Acknowledge the dilemma. Complete the software installation first. During that time, make a limited number of process improvements that don't require massive time commitments. He specifically recommends starting Sales and Operations Planning and working on data integrity. These are consistent with the Proven Path and make the eventual ERP implementation easier.

Nova: : So he's not dogmatic. He acknowledges that real-world constraints sometimes prevent the ideal approach.

Nova: Totally. Once the software is installed, the company transitions from a dilemma company to a Type 1 company, one that already has the software and is ready to implement ERP for real. At that point, the Proven Path applies completely, probably in the Quick-Slice variant. One of Wallace's associates, Bob Stahl, put it well: "The Proven Path was sound fifteen years ago, before the onset of enterprise software. It's every bit as sound today."

Nova: : Let me pivot to something the book covers that a lot of implementation guides gloss over. What happens after go-live? The book has a whole section called Beyond ERP Implementation.

Nova: Yes. Chapter 15 is about Operating ERP, and Chapter 16 is called The Strategic Future. Wallace and Kremzar are clear that going live is not the finish line. It's not even close. They talk about Phase III, the strategic future, where ERP becomes the platform for advanced supply chain integration, deeper customer collaboration, and e-commerce. The book was published in 2001, right at the dawn of e-commerce, and Wallace saw ERP as the essential foundation for any serious online business.

Nova: : He was prescient about that. Without integrated planning and accurate data, an e-commerce storefront is just a pretty face on a broken back end.

Nova: Exactly. The book also includes practical appendices: the fundamentals of ERP for reference, a sample implementation plan, and a glossary that draws on Wallace's work editing the APICS Dictionary. And throughout the book, there's a recurring emphasis on a quote that I think captures the philosophy perfectly: "The cost of control obviously should not exceed the cost of inaccuracies." In other words, don't build elaborate controls around bad data. Fix the data.

Nova: : That's a quote you could put on a poster in every operations department in the world.

Nova: It really is. And that brings me to what might be the most important thing about this book. It was written in 2001, but it's still widely cited in academic papers, still used in university syllabi, still referenced in implementation guides. What Wallace and Kremzar captured isn't a moment in technology. It's a timeless truth about organizational change: the software is the easy part. The people are the hard part. And the people are also the only part that matters.

Nova: : The book's closing words, interestingly, are simply: "Go make it happen!" Which is both the title and the mission.

Nova: Yes. And Thomas Wallace spent his life making it happen for thousands of companies. He delivered seminars to over ten thousand executives across the US, Canada, the UK, and Australia. His books have been translated into Chinese, Korean, Italian, French, Russian, Thai, and Portuguese. His impact on global manufacturing and supply chain management is genuinely immeasurable.

Nova: : It's rare to find a business book that's both a practical field manual and a philosophical reorientation. Wallace and Kremzar basically told the entire industry: you've been thinking about this backwards. Stop obsessing over which software to buy and start obsessing over how your people make decisions. That message, I suspect, is even more relevant today than when it was written.

Nova: So let's bring it all together. Thomas F. Wallace and Michael H. Kremzar's ERP: Making It Happen is not really a book about enterprise resource planning in the way most people use that term. It's a book about organizational transformation disguised as an implementation guide.

Nova: : The central insight is deceptively simple: ERP is not software. It's an enterprise-wide set of management tools, processes, and decision-making frameworks that balance demand and supply across every function. The software is just the golf clubs. You still need to learn how to play.

Nova: The book gives us the Proven Path, a methodology refined over decades of observing what actually works. It gives us the Quick-Slice approach for resource-constrained organizations. It gives us the Class ABCD system for honestly assessing where you are. And it gives us the critical focus on Sales and Operations Planning as the engine that drives everything else.

Nova: : If there's one actionable takeaway for someone listening today who is either considering an ERP implementation or in the middle of one that feels stuck, what would it be?

Nova: I'd say it's this: Ask yourself whether you're implementing software or implementing better business processes. If your project plan is primarily about configurations, customizations, and go-live dates, you're probably missing the point. The harder questions are about education, data integrity, cross-functional processes, and whether leadership is truly committed to changing how decisions get made. Wallace said the ABCs are people, data, and computers, in that order. The computer is item C. Don't put it first.

Nova: : And never try to outsource the people part. Implementers must equal users. Nobody knows your business like your own people, and nobody else has the authority to change how things work.

Nova: Wallace passed away in March 2021 at the age of 85, but his work continues to shape how thousands of companies around the world manage their operations. His books remain essential reading, and his famous line about putting the moose on the table remains one of the best pieces of advice for any executive: surface your biggest problems, deal with them directly, and build systems that make that possible.

Nova: : The book ends with a simple imperative: Go make it happen. And after spending time with Wallace's ideas, that feels less like a motivational slogan and more like a clear, practical instruction. You have the Proven Path. Now go walk it.

Nova: This is Aibrary. Congratulations on your growth!