Both notable persons, Prof. h.c. Wolfgang Mewes, the inventor of the “Engpass-Konzentrierte Strategie EKS®” and Dr. Eliyahu Goldratt, inventor of the “TOC – Theory of Constraints”, have developed system oriented methodologies to improve the situation of companies.
Today the EKS® is a registered trademark of the Malik Management Zentrum St. Gallen AG, Switzerland.
In English language the “Engpass-Konzentrierte Strategie EKS®” is known as the “Minimum Factor-Focused Strategy”  or as the “BCS (Bottleneck Concentrated Strategy)”.
In this article, I will show some commonalities and differences between both approaches, because both have had a strong impact on my work and life.
Both approaches have at least three crucial elements in common:
- both see companies, organizations, etc. as systems,
- both focus on the bottleneck of the system, and
- both put the search for the most important cybernetic leverage point at the center of their consideration.
Because of this overlap, there are often misunderstandings in the interpretation of both approaches, up to the statement that both methods are identical. However, that is not correct. On the contrary, both approaches complement each other in an excellent way from my point of view.
“Minimum Factor-Focused Strategy”
Prof. Mewes suggested to clarify all internal resources, skills, competencies, etc. at first. In a second step, he recommended to map the results with the needs of a narrow target group of potential clients. These two tasks should give orientation.
As the third step, he recommended to seek for the bottleneck at the customer or in the target group. Now a difficult step follows. The development of a specific problem solution for the bottleneck. Such a solution is finally the adequate niche offer for the target group. Furthermore, this approach helps to find the company his own market position by specialization of problem solution for narrow target groups.
I think Mewes would agree to the same bottleneck / constraint definition from Goldratt:
“Constraint – The factor that ultimately limits the performance of a system or organization. The factor that, if the organization were able to increase it, more fully exploit it, or more effectively subordinate to it, would result in achieving more of the goal.” 
Mewes took a broad approach to identify the constraint of the system. He did not focus on specific constraints in operations or other application areas. For him, problems were often hidden and not easy to detect. He wrote in his article on "Das Kybernetische System" :
Translation by Juergen Kanz:
"It has been shown that the problems of man and companies can be divided into the following problem areas:
- Material or logistical problems
- Technical problems
- Economic problems
- Financial problems
- Informal and mental problems
- Problems due to given command structure
- Tension problems (at the bottleneck)
- Strategy problems"
It goes on by saying: "If you solve a central core problem, a multitude of other problems automatically resolve themselves."
During the last decades, a large number of German-speaking companies learned and implemented the method. According to independent researches, the Mewes method laid the foundation for the commercial success of many so-called HIDDEN CHAMPIONS, especially in the SME sector.
Apart from learning material, Mewes did not share tools or other stuff that could help on a tactical level.
TOC - Theory of Constraints
Dr. Eli Goldratt (inventor of TOC - Theory of Constraints) was much more operations oriented. One of his objective was to “make more money now and in future” by improving the performance of the operations system with the focus on the constraining factor. Therefore, he focused mainly on the company internal bottleneck(s) to improve the effectiveness of the entire system.
Many sold books and amazing implementation stories are telling the success of his method in different application areas.
Goldratt did something else in addition. He transformed the logic based causality thinking from the hard sciences into the management area.
He suggested to apply the systemic thinking in cause-and-effect relationships in almost all areas of life. Because of his work, he defined the TOC-Thinking Processes as a tool to go for a change. These tools can help us not only in operations areas, they can help us also in identifying and solving of all kind of problems as above mentioned by Mewes. Both, Mewes and Goldratt, saw the necessity to find the core problem – usually a conflict – and to solve it.
Just to mention it: Goldratt did not talk about problems; he spoke about undesirable effects (UDEs) or symptoms of the actual core problem.
What can we learn?
Enthusiasts of the “Minimum Factor-Focused Strategy” can make use of the TOC generic operations solutions, in case the customer’s bottleneck lays in one of the TOC application areas like Project Management, Manufacturing, Replenishment, etc.
Furthermore, they can make use of the TOC-Thinking Processes to identify the core problem and to find breakthrough solutions for their clients.
While TOC Enthusiasts can expand their service and or product portfolio by making use of the Mewes method. In combination with the TOC-Thinking Processes, they will gain the opportunity to enter new market areas.
At the end both groups should be able to find their own “Blue Ocean”.
Interested readers can find some literature on my page "Recommended Books".
 Strategy - Navigating the Complexity of the New World, Fredmund Malik, https://www.malik-management.com/wp-content/uploads/2017/09/malik-eks_dynamic_specialization-2016-1.pdf, last accessed on October 17th, 2019
 THE TOCICO DICTIONARY, Second Edition, 2012, https://cdn.ymaws.com/www.tocico.org/resource/resmgr/dictionary/tocico_dictionary_2nd_editio.pdf, page 28, last accessed on October 17th, 2019
 "Das kybernetische System", Prof. h.c. Wolfgang Mewes, StrategieJournal 02-08, Seiten 8 bis 11