Clients and selected case studies

28 organizations. One question.

What is the one thing that, if changed, would lift the whole system? Every project below started there.

Some answers were obvious only in hindsight. Others were counterintuitive enough that leaders wanted to test them first, safely, in a simulation or Digital Twin, before risking them in the real world. Which kind of answer is your organization waiting for?

“We faced increased complexity leading to increased inventories, markdowns, and lower service levels. We reached out to GRL, and the outcomes of that work have been nothing short of remarkable.”
Robert Meshew, CTO Global Digital Supply Chain, Microsoft
“We worked with GRL to develop a new replenishment model in a highly dynamic environment. Our initial results were fantastic, and we will surely achieve our zero-emergency order target.”
Annette Danek, Senior VP, Random House
“We worked with GRL to see the impact of our decisions in a safe environment. The Enterprise Digital Twin is a momentous approach and is now an integral part of our Industry 4.0 strategy.”
Bimlendra Jha, CEO, Tata Steel UK

High tech and robotics

Can a supply chain be fast and lean at the same time?

United States · Supply chain simulation

Microsoft

$250M+

Inventory reduction, with service levels up 5%

The challenge

Design, test and implement a TOC-based end-to-end supply chain solution for Microsoft's global digital supply chains within SAP, cutting shortages and surpluses at the lowest cost and inventory.

The result

A self-configurable simulation proved the new rules would outperform the old ones. The solution went live in SAP in a record 3.5 months. Within the same financial year, inventory fell by over a quarter of a billion dollars while sales rose by a few hundred million through fewer shortages and markdowns.

United States · Drum-Buffer-Rope and buffer management

Cisco Systems

43%

Shorter lead times, from 37 days to 21

The challenge

Reduce lead times and improve due date performance across a complex high-tech supply chain.

The result

Lead time variability narrowed from 10 to 115 days down to 12 to 26 days. Inventory fell 40%, from $300M to $180M. Expediting costs dropped 75%, from $60M a year to $15M, and throughput rose 30%. This engagement also gave birth to the Cumulative Flow Diagram.

United States · Project Portfolio Digital Twin

Amazon Robotics

Faster, cheaper

Project schedules optimized for time and cost

The challenge

Plan and execute complex technology projects under tight resource constraints and constantly changing plans.

The result

The Project Portfolio Digital Twin found the shortest, lowest cost schedules, exposed the largest causes of avoidable delay, generated resource demand charts automatically, and let teams test what-if scenarios as plans changed, backed by Critical Chain Project Management (CCPM) support.

Engineering, energy and construction

What if the plan is already late, and nobody knows it yet?

Switzerland · End-to-end supply chain design

ABB

15 to 50%

Better due date performance and throughput in pilots

The challenge

In 2007, hundreds of different ERP systems made it almost impossible to support business units or spread best practices. ABB asked Dr. Alan Barnard to design one TOC-based solution for its One Simple ABB program in SAP.

The result

Within three months, a simulation-tested design covered every fulfillment strategy from engineer-to-order to make-to-stock. Pilots in 30 of 300+ facilities raised due date performance and throughput by 15 to 50% while cutting inventory and lead times by 15 to 50%.

Europe · Project Portfolio Digital Twin

Siemens Gas Turbines

$286M

Swing, from a portfolio headed for a $181M loss back to profit

The challenge

A five-year portfolio of over 100 programs and thousands of projects, priced on reliability with late-delivery penalties, began slipping a year in. Would the buffers be enough?

The result

The Digital Twin confirmed leadership's fears: many programs would finish late and over budget. Testing ways to control work-in-progress (WIP) to focus resources and speed up flow found a strategy that returned the portfolio to profit, a $286M swing.

Japan · CCPM and Project Digital Twin

Daiwa House

6 months early

SAP project delivered, saving US$10M

The challenge

Deliver a major SAP implementation within budget, then shorten construction project lead times.

The result

Using Critical Chain Project Management, the SAP project finished in 18 months against a 24-month plan. The construction team then used the Project Digital Twin to find avoidable delays, cutting project lead times by 5 to 15%.

Metals

How do you test a new rule in a steel plant without risking the steel plant?

United Kingdom · Enterprise Digital Twin

Tata Steel Europe

Lower cost per ton

Higher throughput, lower WIP, rules automated in SAP

The challenge

Test new and potentially counterintuitive planning and execution rules across the entire UK supply chain before committing them to SAP.

The result

A Digital Twin of the whole supply chain, plus three detailed models, found the best ways to relieve congestion at peak production and significantly lowered cost per ton. Management gained a safe environment for ongoing decision support.

India · Plant simulation

Tata Steel: Output Increase

+15%

Throughput within 12 months

The challenge

Find the lowest cost, lowest risk changes that would reliably raise one plant's output by 15%.

The result

The target was achieved within 12 months, worth hundreds of millions per year in additional sales.

India · 2D and 3D dynamic simulation

Tata Steel: Production Rules

Risk-free

Testing of planning, release and priority rules

The challenge

Understand bottlenecks, statistical fluctuations and interdependencies across the plant, and the effect of changing how work is planned, released and prioritized.

The result

A high-level 2D model and a detailed 3D model let Tata Steel find critical bottlenecks and test strategies to raise throughput, reduce output variation and improve reliability.

United States · Plant simulation

Novelis

+19 kt

Annualized throughput, with lead time 3.2 days shorter

The challenge

Increase throughput and reduce lead time at the Oswego plant.

The result

Shorter cooling times, faster automated guided vehicles and packing lines, WIP caps and better scheduling logic. Image processing cut sampling time by 30%, reducing unplanned downtime by 13%.

India · Supply Chain Digital Twin

Jindal Steel and Power: Product Mix

Higher EBITDA

From an optimized product mix across the network

The challenge

Maximize cash flow by choosing which products to run through which processing centers, given production rates, transport limits, equipment availability and demand.

The result

A more realistic optimal product mix, faster scenario creation and the best production routes, maximizing throughput of high-value products.

India · Scheduling tool

Jindal Steel and Power: Caster Scheduler

More casts

Higher daily casting throughput at Angul

The challenge

Allocate hot metal from the blast furnaces to the casters, within the limits of grade, width and length, and automate a slow scheduling process.

The result

Optimized caster campaigns with less overproduction and loss. Integrated with the manufacturing execution system (MES), giving better capacity estimates and more accurate delivery dates.

India · Materials handling simulation

Jindal Steel and Power: Raw Materials

Gaps found early

Before the planned upgrades were built

The challenge

Would planned upgrades to the Angul raw material handling system, from offloading to conveyors, stackers and reclaimers, meet demand in FY25 and beyond?

The result

The model revealed missing paths from several beds to the new blast furnace and showed that, without further upgrades, the plants could not be kept fed without stockouts.

India · Rail logistics simulation

Jindal Steel and Power: Rail Operations

4x growth

In output, without rail becoming the constraint

The challenge

Make sure Angul's rail operations, from train arrival through shunting to rake loading, could handle projected demand.

The result

Scenario tests set the right number of shunting locomotives and evaluated new tracks and rake mixes, removing inbound and outbound bottlenecks to support four times the output.

Mining and explosives

Push or pull? Which one actually moves more?

Canada · Supply chain design simulation

BHP Billiton: Potash

$100s of millions

In additional contribution from the optimized design

The challenge

Find the best potash supply chain design: how much mine, port and hub storage, and how many rail car sets.

The result

The simulation designed and validated a pull-based strategy that beat the traditional push model on both effectiveness and efficiency.

South Africa · Company-wide TOC

African Explosives (AEL)

+400%

Profit, with revenue doubled in four years

The challenge

Turn supply chain reliability and rapid response into a decisive advantage against competitors who competed mainly on price.

The result

TOC planning, execution and improvement implemented company-wide in SAP. The world's first use of CCPM to roll out every SAP module across all businesses worldwide, in record time.

South Africa · Mine scheduling simulation

Jindal Mining Africa

Less downtime

More productive schedules at the Kiepersol coal mine

The challenge

Run efficient operations and make the best use of resources across every section of the mine.

The result

A flexible scheduling and simulation model tested scenarios section by section, finding the most efficient schedules and showing how each decision affects resources and output.

Publishing

Why do too many books and too few books happen at the same time?

United States · Replenishment in SAP

Random House Publishing

Fewer lost sales

And fewer write-offs, on the way to zero emergency orders

The challenge

Reduce shortages and surpluses, not only in Random House warehouses but at retailers too.

The result

A measurable drop in avoidable shortages, and in the surpluses that drive discounting and write-offs at distribution centers and retailers.

United States · Distribution design

Macmillan with ReaderLink

Fewer returns

And lower inventory, proven in virtual and live pilots

The challenge

Reduce surplus stock, especially the initial quantities sent to regional distribution centers and retailers.

The result

Measurable reductions in inventory and returns, first in a virtual pilot and then in an actual one.

United States · Network optimization simulation

Scholastic

Bigger savings

Than expected, from a redesigned transport network

The challenge

After COVID, two consulting firms proposed new network designs using static optimization. Scholastic was not confident they would hold up in the real world.

The result

Simulation showed the proposed design would raise transport costs, not cut them. With PTV Group's vehicle routing engine embedded in the Digital Twin, GRL found and removed the highest cost drivers.

Food, retail and consumer goods

Is it possible to sell the same with less stock?

South Africa · Viable Vision turnaround

Premier Foods

7,300%

Increase in enterprise value over five years

The challenge

In 2008, turn a loss-making bread and flour producer into an industry leader in profitability.

The result

Dr. Alan Barnard led the team that implemented TOC across mills, bakeries and distribution, supported by a Throughput Accounting simulation for product mix and transport choices. The largest growth of any company on the Johannesburg Stock Exchange in that period.

Japan · Supply Chain Digital Twin

Nike Japan

−35%

Inventory, freeing $2.8M in working capital

The challenge

Quantify the impact of new replenishment rules in four stores: Harajuku, Shibuya, Fukuoka and Osaka Running.

The result

TOC Dynamic Buffer Management cut sales at risk by 24%, to just 0.2% of total sales, with fewer stockout days across equipment, footwear and apparel.

United Kingdom · Retail simulation

Ralph Lauren

8 to 6.5 weeks

Of inventory, for the same revenue

The challenge

After a successful 2021 proof of concept, measure the value of TOC dynamic buffers on 40 representative items at the Bicester store over a full year.

The result

Less sales at risk, fewer stockout days, higher inventory turns and return on investment (ROI), and cash freed for assortment optimization.

United Kingdom · Import and distribution simulation

Cargill Meat Europe

8 to 6.5 weeks

Of inventory, with service maintained or improved

The challenge

Improve availability and inventory management across the import and distribution supply chain, from forecasts and orders to transport and replenishment.

The result

New TOC inventory rules balanced stock across distribution centers and pointed to further gains from changing lot sizes and order frequencies.

Mauritius · TOC and DDMRP simulation

ChemTech

+57% ROI

With inventory turns up 51%

The challenge

Close the availability gap by applying TOC and Demand Driven Material Requirements Planning (DDMRP) to the supply chain.

The result

Fewer shortages and surpluses, with revenue up 6% and net profit up 8%, all without adding inventory.

Government and NGOs

Can a government move faster without a bigger budget?

There is no profit motive and no competitor forcing change. Many would say that makes the public sector harder to improve. Or does it simply mean the constraint is somewhere else?

United States · Statewide productivity

Utah Governor's Office of Management and Budget

25%

Average productivity gain across 24 agencies in under 12 months

The challenge

Under Governor Gary Herbert, improve performance across 24 independent state agencies without central authority or a crisis to force change.

The result

Each agency chose ONE goal (more, faster, better or cheaper) and found its constraint, all measured against one shared target. A four-year goal was reached in under a year. DMV waits fell from 45 to 10 minutes, environmental permits from six months to six weeks, recidivism by 30%, and Transportation delivered 40% more road maintenance on the same budget.

Zambia · Municipal services

InWEnt and Lusaka City Council: Solid Waste

85%

Household participation, with 90% sorting accuracy in the pilot

The challenge

Overflowing waste and rising health risks, driven by unreliable fee collection in low-income areas, inefficient collection routes and little citizen participation.

The result

Using ProConCloud, the community co-designed win-win strategies: revenue sharing with local NGOs, sorting incentives and micro-recycling that turned waste into a community resource. Coverage expanded in underserved areas, and the city adopted Minimum Viable Experiments to scale up with minimal risk.

Italy · Humanitarian value chain

United Nations World Food Programme

30 to 50%

Potential lead time reduction in pilot processes, on the same budget

The challenge

With SAP, help the world's largest humanitarian agency turn donor funds into food delivered to people faster, across fundraising, programming, procurement, logistics and distribution.

The result

The core constraint was the slow matching of donor-directed funds to actual deliveries. GRL designed an integrated TOC flow model, a real-time constraint dashboard concept and a central funding buffer for faster emergency response with full donor transparency, so WFP can feed more people, faster.

Which of these looks most like your situation?

Every one of these organizations started with a goal that felt out of reach. Tell us yours, and we will help you find the one thing to focus on first.

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