’’Although my great drawing skills that came naturally to me were doubled by a passion for ornamentation and decoration, I later became the advocate of simple architecture, lacking abundant embellishments, which through right proportions and harmonious plasticity, was to give the utmost satisfaction to both sight and reason.’’
(Duiliu Marcu, Arhitectură 1912-1960, Editura Tehnică, Bucharest, 1960, p. 16)
’’Based on the work experience I had gained between 1912 and 1930, while examining my position concerning the two movements (classical and traditional), I realized that it was not the best path I could take and I had to change my view on our architecture radically [...] The architecture of the past belonged to the past; the present required something different from architects. [...] For these reasons, ever since 1930, I have strived to find my way, seeking for a modern Romanian architecture to which I have tried to give the most original forms possible.”
(Duiliu Marcu, Arhitectură 1912-1960, Editura Tehnică, Bucharest, 1960, p. 20)
’’My interest in finding original solutions, typically Romanian, in taking from classical architecture only clarity, simplicity, balance, eurhythmy, proportions, meticulous detail studies, and the precision of execution [...] was for me a model of conduct, a belief that has guided me throughout my career. This was the background of my work [...] Have I succeeded? I can say [...] that I am far from being always happy with my accomplishments.’’
(Duiliu Marcu, Arhitectură 1912-1960, Editura Tehnică, Bucharest, 1960, p. 21)
’’The Romanian pavilion seems one of the best in the exhibition; through its monumental appearance, it manages to transfer its appearance to Trocadéro esplanade; through its forms, it is in harmony with large pavilions...; through its layout, it is perfectly suited to its role; the great hall of the pavilion allowed the opening ceremony to gain full extent, with unencumbered access. Dl. Duiliu Marcu adroitly used Romanian materials, highlighting them thanks to modern technology and reminding us, through forms and ornamental motifs, of the traditions of both academic and popular Romanian art."
(„Arhitectura pavilionului român”, in: Beaux-Arts journal, Paris, 1937)
’’A remarkable artist is always an exemplary artist, a seeker of beauty through truth, and we can readily acknowledge this quality in architect Duiliu Marcu whose entire work speaks about his clarity of thought, harmonious nature and patriotic dedication.’’
(Tudor Vianu, Duiliu Marcu – Arhitectură, 1912-1960, Editura Tehnică, 1960, Bucharest, p. 13)
’’Duiliu Marcu’s work cannot be understood and could not even have been accomplished without the ‘problem of the construction site.’ It was an essential issue for him. He could only find peace after completing the work with the people he had personally selected or accepted, whom he then began to press and pester. The master used to say: ‘Each work site should be treated like a child. First chide, persecute and educate him – only then praise and press him again.’’’
(Adrian Oprea, „Duiliu Marcu 1885-1966”, in Arhitectura magazine, no. 4/ 86, Bucharest, p. 62)