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Article Abstract: The forty years since the establishment of the British Concrete Society roughly cover my research career. Over the past four decades, significant changes in the concrete industry have had a substantial impact on the types and volume of research conducted, which can be summarized into two main aspects. Preface: For the concrete industry, the 1960s was a period filled with optimism and ambition. Although reinforced concrete was already in use before World War II, its true rise to prominence came in the late 1950s and 1960s. The reasons are, first, a shortage of steel, and second, the need for major redevelopment of the city center. It was a golden age for residential and commercial buildings, not to mention road construction projects... Introduction For the concrete industry, the 1960s was a period filled with optimism and ambition. Although reinforced concrete was already in use before World War II, its true rise to prominence came in the late 1950s and 1960s. The reasons are, first, a shortage of steel, and second, the need for major redevelopment of the city center. It was a golden age for residential and commercial buildings, not to mention the planning of road construction projects. At that time, due to financial constraints, as well as the construction industry’s focus on increasing construction speeds, many experimental solutions turned towards concrete structures. Perhaps the most notable of these was the development of various modular building systems for multi-story buildings. Peaks and troughs: Concrete. In the mid-1970s, problems arose in some structures built during the golden age of the 1960s. The partial collapse of the Ronan Point building in 1968 marked the beginning of the disillusionment with high-rise buildings. Although many problems are not structural issues, but rather result from construction, social factors, and perhaps inadequate maintenance. In the field of concrete, the subsequent research topic is durability. The various problems that arose in concrete structures, along with the increasing availability of cheap structural steel at that time, led to a period of decline and uncertainty for concrete structures. It was not until the mid-1990s, that is, in the past decade, that concrete buildings gradually regained their former confidence, allowing us to see once again more innovative designs and applications of concrete structures. Reinforcing bars: The second major change relates to the properties of reinforcing bars and concrete. Although the use of high-strength rebar has been permitted for a long time, reinforced concrete structures built before World War II and in the late 1950s mostly used low-carbon round rebar with a yield strength of around 250 Mpa. By the time the British Concrete Society was established, things had changed rapidly, and steel with a yield strength of 410 or 460 Mpa had become a standard material. However, practical experience remains limited to low-carbon steel. Over the years, the strength of steel has been increasing steadily; currently, the strength of ordinary steel can reach 500 Mpa, while it is also possible to reduce the safety factor. Therefore, the current grades for steel bar stress values that we use are twice as high as those based on our long-term experience in the early days. Since the elastic modulus of steel does not change with its strength, the cracks and deformations that occur in components of a certain size will be twice as large as those in the initial stage. Cement: Cement has also seen significant changes. Currently, the strength of Portland cement is also much higher than it was in the early days. Furthermore, in the 1960s, concrete was generally prepared using ordinary Portland cement, aggregates, and water. However, modern concrete contains various admixtures, such as powdered fly ash (PFA), microsilica, or kaolin, as well as additives such as superplasticizers. Concrete has become a material that is completely different from the past; it is now a material with a higher degree of \"high-tech\" characteristics. In the early 1960s, the strength grades of conventional concrete structures were 21–28 Mpa; today, structural concrete with a strength lower than 30 Mpa is rarely seen. Typically, concrete has a much higher strength. Premixed concrete suppliers are now able to produce concrete with a strength of over 100 Mpa; compared to the concrete used in earlier times, this is a completely different material. Research work: Structural research. In the late 1950s and 1960s, research on structural concrete was quite widespread. During this period, the characteristic of the research work was a focus on understanding the behavioral properties of materials; many large-scale experimental research projects were carried out. Here, two such research projects are cited as examples for brief explanation. Perhaps the most ambitious research project among them is the study on the toughness of reinforced concrete sections, organized by Professor Baker of the Royal Academy and sponsored by the European Committee on Concrete. This study attempts to establish redistribution rules for reinforced concrete, almost developing a method for the plastic design of structural steel. 16 laboratories worked together to carry out this research. The research results come from approximately 170 reinforced concrete beams. The practical outcomes of this research work are already incorporated into the redistribution rule provisions of the CP110 code and the BS8110 standard. The second research plan is a survey and study on crack control conducted by the Cement and Concrete Association. The first research report on this project, which involved 105 reinforced concrete beams, was published in 1966. Subsequently, several more research reports were released one after another. More than 200 reinforced concrete beams were involved in the research, and tension tests were conducted on them. The outcome of this research project was the derivation of the crack control formulas listed in the regulations published successively in the UK. A by-product of this research work is the deflection calculation method and the effective span-to-height ratio. This British research project is merely a microcosm of the extensive crack studies conducted during that period on a series of large-scale projects in the UK, the US, and Europe. In the 1970s, the concrete research conducted using this approach had its data widely incorporated into the database used by the standard drafting committee, thereby enabling the development of effective design methods. The procedures drafted during this period were all based firmly on a large amount of data obtained from experiments. By the late 1970s and 1980s, large-scale research on structural concrete essentially came to a halt. There are many reasons for this, but the main factor is the increasingly tight funding for universities and other research institutions ； The concrete industry believes that all the behavioral characteristics of concrete structures required by them have been thoroughly studied ； The focus of research funding has shifted from structural research to durability research, which should be given higher priority. This is not to say that research on structural concrete has come to a complete halt; for example, research on shear forces remains a continuously popular and active area of study. From a historical perspective, an interesting phenomenon is that resilience is once again becoming a topic of interest. Early studies conducted by Professor Baker showed that the ultimate failure of concrete structures is often due to impacts on those structures, whereas structural failure caused by the breaking of rebar can be disregarded. However, recently Professor Eligehausen in Stuttgart, Germany, and his colleagues conducted a study based primarily on nonlinear computer analyses of the plastic hinge zones. The research findings suggest that the aforementioned conclusion is no longer correct. Some modern processing techniques produce steel that is more brittle, leading to damage to concrete structures due to the fracture of the steel. Furthermore, compared to the concrete studied by Professor Baker, concrete with higher strength today tends to be more brittle. Therefore, due to changes in concrete production and steel manufacturing processes, the data collected during Professor Baker’s main research period is now outdated. If the design rules are to be updated, similar research work must be repeated. In modern times, it is unrealistic to organize an international collaborative research project like Professor Baker did. However, such research can be conducted within several **regions (including the UK). A task force established by the European Committee on Concrete, led by Professor Eligehausen, provided an academic forum to discuss these research findings, and published a research report of advanced technical level in 1997. This report led to revisions in European codes regarding concrete brittleness, requiring consideration of steel fracture and increasingly higher strengths in the design rules for toughness and capacity distribution. Recently, another major research area that has seen successful development is the design of fiber-reinforced composite materials and more innovative repair methods. Durability: Over the past four decades, a major shift in research focus has been the increasing emphasis on the durability of concrete, for reasons that are well known. From the late 1950s to the early 1970s, during that golden age of construction, durability issues were not recognized by *established interests. It was not until the mid-1970s that problems arose in some of the building structures constructed during that period, and a series of obvious issues came to light: the transformation reaction of high-alumina cement (HAC) led to a significant decrease in strength. Although this reaction is well-known, it had not been recognized that it occurs under British environmental conditions. Studies on the collapsed roof beams of Camden College indicate that this may require a thorough assessment of the extent of damage to all buildings containing concrete components made with high-alumina cement. The use of an early-strength agent containing calcium chloride can cause corrosion of steel bars. Using de-icing salts on roads can cause steel reinforcement to corrode. The corrosive effect of chlorides has been known for a long time, but the widespread use of salt on roads became a common practice in the latter half of the 20th century, as transportation shifted heavily from railways to roads. Furthermore, for **reasons**, the main roads must remain open throughout the year. The consequences of this policy were not recognized at the time. Thus, there was a period of about ten years during which de-icing salts were increasingly used on roads, until serious problems of rebar corrosion arose. There are numerous problems of rebar corrosion in the Middle East, which is a region where British designers and contractors are very active ； Alkali-silica reaction—this is a reaction between the strong alkalis in cement and certain types of silicate aggregates. In the past, people did not believe that British aggregates could cause such problems. However, in the late 1970s, such reaction cases also appeared in several areas of the UK. The various attempts to address these problems reflect how superficial the understanding of concrete durability is. Moreover, it is precisely the existence of those design formulas and construction procedures lacking a rational basis, especially in the research on steel bar corrosion—which is considered the most serious practical problem—that has led to a significant shift in research funding toward topics related to durability. Over the past 25 years, durability issues have likely been the most active research topic in concrete. Discussion: I have provided a brief overview of certain areas of research on concrete over the past forty years. What lessons can we learn from this history? Research work can provide a variety of answers to certain specific problems. However, the existence of the problem is the most important thing. It serves as a form of training for experts, enabling them to identify problems and propose new directions for research and development. The integration of such expertise takes a considerable amount of time to develop successfully, but it can also be destroyed rapidly. Funding directed toward research on steering durability will lead to the depletion of the funding that was previously used extensively for research on structural concrete. Almost no experts in structural concrete are able to successfully switch their field of specialization to become experts in durable concrete. Most experts have not also made such a career shift in their field. They realized that their research funding had run out, and their professional careers were over. They either leave research work or retire. However, it is certain that hardly any new researchers are entering this field at present. Although they were not completely destroyed, the pool of experts with knowledge regarding the behavioral characteristics of structural concrete is now very small, and it continues to shrink. It may take another ten years or more to accumulate expertise on concrete durability, by which time the durability problems that existed before the late 1970s will have almost disappeared. Therefore, it will still take a long time to obtain authoritative answers to the currently urgent and practical durability issues. If another new field comes to require priority, funding for durability-related issues will also be diverted, and then history will repeat itself: the expertise in durability acquired through substantial investment will once again be lost. This entire development process seems to be quite resource-intensive in terms of both financial and human resources. However, it is certain that there will always be a balanced medium of expertise capable of covering concrete research and enabling more effective responses to real-world needs. Conclusion Although concrete research has been declining in the UK and Europe for several years, this phenomenon is not global. The proportion of requests for papers on concrete research coming from the Far East (particularly Singapore, China, Japan, and South Korea) has increased significantly. Perhaps we in the UK should pay more attention to concrete research.