1998–1999: remodelling of the ground floor
It involved the creation of the modern Ravens House Conference Complex. The project was designed by Tadeusz Półchłopek and Mirosław Stępień, the architects of the ABP studio. Soon, it grew into a prestigious meeting place not only for the people of science and culture but a venue to celebrate the official state events.

2000-2001: remodelling of the third and fourth floors
The remodelling of the third and fourths floors of the edifice, together with a staircase where the panoramic hydraulic lift was installed, was accomplished without changing the external silhouette of the building and carefully preserving the historical build up from the Middle Ages to the 20th century. The works were conducted in accordance with Romuald Loegler’s conceptions. A bold fusion of heritage and modernity did not only attempt to break conservation stereotypes but heralded a new phase in the development of the ICC,

2002–2003: remodelling of the cellars
The cellars adapted for the ICC’s needs became an example of a successful conservation experiment. A principle of the truth of material consistently applied to the project allowed the integration of carefully unearthed and renovated historical motifs with boldly introduced modern construction and décor solutions. The underground complex consists of three seminar rooms which are a valuable extension to the Ravens House Conference Complex and also turned out to be an excellent exhibition space.

2003: remodelling of the first floor (ICC Gallery)
The outcome of the sophisticated construction works is the ICC Gallery sized approximately 250 m² - an extended space of modernised functional arrangement. The exhibition space was equipped with modern services and systems which permit museum exhibitions.

2003–2005: remodelling of the second floor
While refurbishing the offices on the second floor of the building, the structure of the ceilings was reinforced. Moreover, new telecommunication and technical facilities were installed. The Seminar Room of the second floor is not only one of the institution’s showpieces, but a place of dialogue with the world conducted on an everyday basis.

The modernisation works also involved an exchange of installations; fire security conditions were also improved; anti-theft facilities and security cameras were installed.