The MÉMOSZ headquarters on Dózsa György Road is perhaps the most outstanding work of a unique period in Hungarian architectural history that lasted only a few years. During this period – roughly between 1947 and 1949 – Modernism, which had already been present in Hungary before the Second World War, completely triumphed. One after the other, designers created buildings that were the most complete embodiments of modern principles. The Erzsébet Square Bus Station and the College of Horticulture and Viticulture (now Buda Campus A of Hungarian University of Agriculture) were built during this architectural "grace time". It was during this period, in 1947, that the National Association of Hungarian Construction Workers launched a design competition for its new headquarters. According to the tender, participants had to provide, among other things, a 1,000-seat auditorium with stage equipment, lounges, meeting rooms, a restaurant, a gym, and, of course, the offices of the union.

At that time, the area around the venue was undergoing a fundamental transformation, with trade unions and various (communist) party organizations moving into the former villas and garden apartment blocks. This was followed by the widening of the former Arena Road bordering the city park for parades, which was completed by the demolition of the Regnum Marianum church and the erection of the Stalin statue. The location of the trade union headquarters was thus integrated into this political-urban planning concept. The result of the competition was interesting: Imre Perényi's development plan and László Gádoros' and Gábor Preisich's joint design had to be "put together", as Gádoros remarked, and other candidates (Lajos Kozma, György Szrogh) were also involved in the design. Kozma, a prominent figure of Hungarian Art Deco, died in 1948, while Imre Perényi was arrested in the summer of 1949 and sentenced to life imprisonment as a co-defendant in the Rajk trial. Despite the considerable obstacles, the design and then the construction progressed fairly quickly, the inauguration took place in May 1950, and the interior work continued for another year.

It was a strange twist of fate that when the headquarters was completed, its modern style was persecuted, and the building, which was otherwise of very high quality, was branded as the worst example of cosmopolitan architecture. At that time, the official style in Hungary and the other countries of the socialist bloc was exclusively socialist, i.e. architecture and art "socialist in content, national in form", which had to be adapted in each country in the spirit of a "progressive" era. In our country this was the classicism of the reform era, in the Soviet Union the baroque of Peter the Great and Catherine the Great (or "Stalinist baroque"), and in Poland the party renaissance that symbolized the country's heyday. It is not difficult to understand that, in this spirit, the curtain-walled façade of the headquarters, the still-modern interior of the Congress Hall, and the spiral staircases that float lightly down the spacious foyer were considered abhorrent, even persecutory. Of course, the Association moved into the building and used it, for it is an excellently laid out building according to modern principles, although its vast common rooms, huge galleried lobbies and corridors seem almost overly generous and spacious compared to modern office buildings.

It is typical of this strange transitional period, and a fundamental characteristic of the buildings of this period, that although they were built in a modern spirit, they were still constructed with an 'old school' fastidiousness, almost in an artisan way – although the new technology of flat roofs and air conditioning (!) was, according to the error correction reports, a mistake of the builders. Otherwise, the marble columns, wood panelling and original cylindrical elevator (now sadly demolished) are reminiscent of the Bauhaus-style apartment buildings of Pest.

The elegance of the building, which was declared a historical monument in 1999, is enhanced by the works of art that accompany it. The sculpture of the Construction Worker, which is currently being restored, stands in front of the façade entrance to the conference hall. Dezső Lányi's statue of the worker who replaced the stone was originally unveiled in front of the former headquarters of the National Association of Hungarian Construction Workers in 1929. The interesting thing about the work is that, according to contemporary photographs, it formed a tight unit with the base of the building, which was inaugurated in 1909, as if the worker had just added another element to the existing stone wall. A piece of this stone wall was placed in front of the new headquarters, where it stood on a red poster until 1999, when it was moved to a nearby garden. After the current restoration work, it will be returned to its original location.

István Tar's artwork on a similar theme entitled “Builders” or “Construction Workers”, a special technique of deep relief, is another work of art that enriches the exterior of the building. The design of the façade of the windowless wall of the conference room facing the Városliget Alley was, according to the minutes, discussed at the planning stage, but was finally covered with limestone from Sóskút with the scene of the construction work engraved into it. The expressive effect of the deep relief is enhanced by the grid of stone slabs that runs through the robust, typically social-realist figures of men and women. This was the first large-scale architectural sculpture by the artist, who had previously made small sculptures and had been a scholar at the Hungarian Academy of Rome between the two world wars. One of the great merits of the current restoration is that the side and rear façades of the Auditorium have been restored with limestone of the same porosity, while the cladding of the main façade has been preserved and restored with the artwork. Since there was originally a layer of air between the structure and the cladding, it was possible to insulate the building in such a way as to preserve the original aesthetics and proportions of the building. Some very important works of art were lost during the demolition by the previous owners. Fortunately, a plaque commemorating the builders and various figures of the labor movement was found and reinstalled in the lobby. What other details remain and how the monument has been transformed for a new purpose and a new future is explored in detail on the following pages.