What is MES?

What is MES? It stands for manufacturing execution system, and is a computerized system that allows manufacturers to track, control, and document processes--from raw materials to finished goods. Being able to manage these processes can greatly improve operational performance on the plant floor.

Manufacturing has been on the MES journey now for over twenty years. Many companies started with big ideas for MES, believing that it was going to revolutionize their plants to provide more automation and visibility. MESA (the Manufacturing Enterprise Solutions Association) attempted to define MES by listing 11 functions of an MES. This was merged with the Purdue Reference Model in 2000 by the ANSI/ISA-95 standard.

The model spans many functions, and this is perhaps where MES is set up to fail. While MES can help improve OEE, it is not the "silver bullet" that was promised from the start.

There may be a more simple approach to getting the majority of the benefit that many manufacturers are looking for from MES without the cost and complexity of a full blown MES implementation.

MES System Benefits

At a high level, MES benefits deliver on three core elements well:

  • Product traceability ("Track and Trace")

  • Recipe Management

  • Machine Process Control


  • Labor Management

  • Regulatory Compliance

  • Supply Chain Visibility

  • Logistics Scheduling & Planning

These capabilities can be very valuable, especially if you are in a highly regulated industry in which the risk of error can be costly or catastrophic.

However, many companies don't have machines with PLCs or they use paper to manage functions such as recipe and trace. Manufacturers want to evolve their sites into digital factories, but don't want to spend years and millions of dollars on a complex MES.

Integrating is also no easy task. The complexity of PLC programming (both from the machine-level instruction and in terms of the skill required by engineering staff) has set a very high threshold that many manufacturers haven’t been able to overcome. Time and money constraints have made it next to impossible.

What an MES Platform Deployment Can't Do For You

MES focuses solely on the equipment and assumes that all problems around manufacturing execution can be solved through sensors and PLC software. In reality, this is a factor, but only accounts for a portion of the operational availability (OA) gap in manufacturing. It neglects to incorporate other critical abnormality management elements such as:

  • Material issues: A glaring gap in MES is the ability to track material issues in your production process. This can include ordering, material shortages, and inventory management. 

  • Training issues: Unlike a cloud-based LES system, an MES does not have the capability to track employee skills training and certifications. 

  • Quality problems: An MES can help manage production, but does not have capability to track and monitor quality assurance. 

  • Audits: Unlike a complete LES system, an MES does not keep track of records and necessary information for Audits.  

  • TPM: Total Productive Maintenance (also known as Total Preventive Maintenance), an MES does not have the capability to monitor your entire maintenance system. 

  • Plus other areas where issues/abnormalities can and will arise such as 5S, product changeovers, trial management, product verification runs, and cleaning procedures. 

Do You Need an MES Platform?

In theory, a MES Platform is designed to define capabilities for managing every element of the shop floor. But it's fallen short.

We've been told that MES can do it all. With enough time and money, it probably could. Of course, we've never come across a plant with unlimited resources.

In addition, due to the climate of global competition, manufacturers have been forced to narrow the MES scope because most implementations have taken many years and millions of dollars. In cases where they eventually do pull the trigger, they typically have portions implemented on the machine side, but the scope has been narrowed so much that they resort back to manual methods for many execution processes never delivered by MES.

Points to Consider when looking to purchase an MES Tracking System:

  • In the digital age we live in, committing to anything that takes 2-3 years to implement is sure to put you behind the times before you even finish implementing.

  • Companies are being sold off and merged so often that they usually are left with a myriad of different MES systems that present additional challenges around consistency of data, process, and integration capability.

  • Many manufacturers are fed up with the seemingly never-ending journey and frustrated that the bill of goods they were sold never materialized.

Part of the complexity is often due to the fact that many manufacturers have a growing list of SKUs with shrinking IT support staff. This creates a conflict between the ongoing support of MES and other competing IT projects. We’re not saying implementing MES can’t or shouldn't be done, but you should know what it will accomplish and what it won’t.

Why an MES Tracking System Isn’t the Perfect Solution:

The PLC Problem 

Historically, machines were operated by people who monitored production and performed visual inspections to maintain quality. They identified the manual adjustments necessary to restore the process back to a controlled situation.

This was during a time when it wasn’t uncommon to have multi-decade veteran employees who performed the same jobs their entire career. In today’s environment, workers and jobs change with much greater frequency, making it difficult to maintain consistency in productivity and scrap control.

As manufacturing processes have become more automated and sophisticated, the ability to remove variance and mistake-proof processes has been critical in increasing productivity, reducing scrap, and minimizing wasteful over production. This is accomplished by automatically adjusting for variation of product attributes and machine parameters, such as:

  • Dimension

  • Weight

  • Verification/inspection data

  • Machine settings

  • Etc.

By building this functionality into the process, you thereby have a standard to measure against. This gives you the ability to know when the process has drifted out of normal operating conditions and notify the operator that a problem has occurred.

These capabilities can be very valuable, especially if you are highly regulated and the risk of error can be costly or even catastrophic.  

However as mentioned above, many companies aren't in that boat. Some don’t have machines with PLCs, or primarily use hand tools for assembly. Others may have these things, but they are currently using paper to manage items such as recipe and trace. These manufacturers don’t want to spend years and millions of dollars on a complex MES, but still want to evolve into a digital factory.

Lack of Standardized Approach

An MES platform comes up short by only identifying and surfacing problems. What you need is a standardized approach that allows you to focus on systemic issues and resolve problems.

Often, there is no system in place to manage the follow-up and corrective actions, therefore the ball is often dropped and companies struggle to close the loop on common problems in their facilities. This puts additional burden on your key resources, as they are constantly fighting recurring plant floor issues. 

Real-world example: Cars are getting more and more sophisticated every day, but they still rely on the operator. The computer in the car can tell you that the air in your tires is low, but it can't tell you that the tires aren't wearing evenly because you have a bad shock. Often, trying to use sensors to capture everything is just not cost-effective. Thinking you will eliminate the driver from the equation at this point is really just crazy.

Minimal Impact on Problem-Solving

It’s important to first know what your problems are. It's not unusual to find that many companies struggle with common problems like: 

Often there are as many as two hundred processes and subprocesses in manufacturing, many of which are managed with manual methods such as paper, radios, and post-it notes.  

Let's say OEE for your plant is at 65%. If you were to break out the 35% difference between where you are and 100%, how much of the opportunity can be solved by MES? 

Often, putting processes and software in place to help bridge the gaps outside the basics of machine control can deliver huge gains without breaking the bank. Putting all of your eggs in the MES basket may leave you wanting more when you don't get the improvements you had hoped for. This is why we see the promise of MES failing in most organizations.


If Not MES, What is the Alternative?

Maybe you still need a full-blown MES platform, maybe you don’t. Either way, the good news is you have options. Manufacturing is really about creating an efficient, consistent, and repeatable process. 

Not only the actual manufacturing process but also all of the sub- and micro-processes that support the value-added process. Do yourself a favor—understand the process gaps in your facility and determine which of them has the greatest impact on your bottom line.  

Successful companies can bridge a significant portion of that OEE gap by focusing on abnormality management. This means that anywhere a problem is likely to occur, they implement a closed loop digital system like L2L’s CloudDISPATCH to streamline and solve problems at all levels. The good news is that CouldDISPATCH can integrate with every major MES solution in the market

In order to achieve your objectives, you may still find it necessary to implement an MES solution. There is a wide array of companies available to provide this service, or you may have chosen to build it yourself. It’s becoming more cost-effective to outsource as companies have been deploying MES for a while now. It’s critical, however, to be clear on what you’ll be able to achieve vs. a promise that can’t be fulfilled.

You should now have a better understanding of what MES can deliver, and what MES often promises, but fails to deliver. Many leading companies are achieving the efficiency they need through L2L’s Lean Execution System (LES). This way, they’re able to identify their biggest problems, and put digital processes in place to solve them, realizing significant improvements.  


There are four main aspects of the business that manufacturers have to deal with on the floor every day: Man, materials, machine, and methods.

  1. Man is the people. Both the people who build the product and those who support the people who build the product.

  2. Materials are the components to make the product. The one thing about material is that like it or not, your competitor is probably also buying from the same suppliers and paying probably close to the same prices you are.

  3. Machine is the third one to build the product, but again, like it or not, your competitors are probably buying their machines from the same vendor at close to the same cost.

  4. Methods are how you manage the processes or workflows in the facility, and so this is where you gain a competitive edge; through the methods that you choose to deploy or manage these four main aspects.

When to Focus on an MES Solution

If you feel you need an MES solution, and maybe you do, as they're very good at monitoring machines and material, then just focus the activities on those two aspects for better success.

When it comes to machines, a good MES solution controls the settings or the parameters of the equipment like the fill rate and the speed. 

Next would be the material control aspect of MES. Meaning the components to build the product, the traceability of the lot numbers and/or the serial numbers of those components that go into making the product, from the raw components to the final product.

So, with that being said, it's very costly and time consuming to build an MES system, especially if you want it to control the whole plant. However, sometimes they're very much required by your customers and needed for the traceability of the product. 

When LES is What You Need

An MES can only notify you of the problems related to machines. Our research has shown that these machine related issues typically represent 15% or less of the total issues that occur on the plant floor. With this in mind, the much greater opportunity to drive improvement lies beyond MES. The opportunity to solve the other 85% of your issues is not only critical, but is also extremely valuable. Oftentimes, the lowest hanging fruit is found among the other 85%.

Therefore the smartest approach for many manufacturers is to deploy an LES first.

An LES allows you to achieve improvements in productivity by standardizing the responses to issues, and creating a closed loop on resolving them.

Additionally, an LES provides the continuous improvement foundation on which the MES can sit. And an LES extends MES capabilities for driving improvement. For example:

  • MES data and metrics can be used to trigger processes outside of a machine

  • Machine notifications will have a trackable action or response that’s required in order to close the loop on resolving the issue

  • Provide data interface for operators where no MES data is available (no PLCs, outdated hardware or control systems, manual processes)

  • Processes can be launched across any part of the plant through the LES based on MES data.

L2L’s Lean Execution System (LES)

The good news is that while you have problems every day that need to be solved, you also have the people to help solve those problems. Problems equal opportunities and opportunities are where you become more efficient. The way you choose to manage those problems is how you gain a competitive edge.

The more quickly you can identify those problems (opportunities) and manage the actions around solving the problems, the more efficient you become and the more money you save. 

A good Lean Execution System (LES) system like L2L will help in your problem solving efforts by helping you:

  • Identify the issues and roadblocks on the shop floor

  • Understand each problem you're facing

  • Prioritize those problems and opportunities using data instead of emotions

  • Put actions in place to solve the problem and manage the actions built around them

  • Measure the actions (Review Data) to ensure the problem has been solved (Follow-up)

  • Share those lessons learned with other parts of your plants, or even throughout the company, to eliminate the possibility of the repeat issues

In Summary

Manufacturers are looking to increase productivity. They can achieve this objective by consistently identifying and solving costly problems, and by managing the methods and people to build a continuous improvement culture

LES allows them to do this with a fraction of the time commitment and resources that it takes to deploy and manage an MES implementation. As a result, many companies are either adding an LES as their worker interface on the plant floor, or deploying LES before MES to gain the quickest competitive advantage.

With an off-the-shelf LES cloud solution (Like L2L), the ability to be more agile is becoming a more cost effective alternative. L2L can be deployed and running in your plant in as little as 4-6 weeks.

Bonus Section: MES vs MOM

The terms MES and MOM are very often used interchangeably. While they are both similar concepts, they are not identical. MOM stands for “Manufacturing Operations Management,” and can be defined as a collection of systems for managing end-to-end manufacturing processes with a view to optimizing efficiency. MOM refers to the overarching system or systems in your facility that encompass scheduling, dispatching, maintenance, skills management as well as the functions of MES. In contrast, MES is simply a part of the solution and is rarely the all-encompassing software needed in your facility.

In simple terms, think of it this way: MES (Manufacturing Execution System) + LES (Lean Execution System) = Lean MOM (Manufacturing Operations Management). Combined they offer a comprehensive solution to both the machine issues related to track and trace, recipe management, process control, etc., and all of the human actions/responses to the abnormalities that happen every day on the plant floor.