Conservation treatments described in this master thesis were conducted on the works of art that belong to the Museum of Contemporary Art (MSU) holdings and are displayed on the MSU building. The master thesis deals with conservation and restoration of three different artworks made of different materials. The first topic relates to methods of presenting contemporary posters. Three possible methods of presenting are described; the application of posters on the canvas support, the application of posters on a wooden board using conservative Velcro tape and the application of posters on an acid-free support with magnets, which were demonstrated on the poster Trojanskog rata neće biti by Boris Bućan. The methods were designed for the exhibition of Bućan’s posters, that in various ways unite the visual requirements set by the exhibitions and the exhibition standards in the museum applying the ethical guidelines of the conservation and restoration profession. Within this topic, a general overview of treatments of artworks on paper was made. The second topic covers the conservation and restoration treatment of the mural Open My Eyes That I May See, by the artist OKO, located on the west wall of the MSU plateau. Shortly after its creation, the mural was vandalized with a derogatory inscription that was covered with white paint to hide the inappropriate content. Both interventions disrupted the aesthetics and message of the artwork, so in the accordance with the conservation and restoration guidelines, it was decided to remove the inscription and the white overpaint. For this purpose, various gel-based cleaning systems were tested. After successful removal of non-original parts, an aesthetic reintegration of the painted layer was performed and various graffiti protection coatings were examined. The third topic describes the conservation and restoration treatment of the contemporary easel painting Predeo by Stojan Ćelić. The painting was found in a state unsuitable for an exhibition; without a stretcher, extremely rugose and covered with a layer of surface dirt. Following the principles of sustainability and green chemistry, an appropriate treatment had been devised. Since the painted layer is extremely sensitive, the cleaning was approached with extreme caution, and agar and agarose gels were tested for this purpose. After removing the surface dirt, the painted layer was consolidated and the painting was stretched on an working frame in order to successfully carry out the further conservation-restoration. Eventually, the missing colour reintegration was performed and the painting was stretched on the new stretcher. The treatments were designed and performed under the professional guidance of Assoc. prof. mr. art. Neva Pološki, Head of Conservation Department of the MSU, Mirta Pavić, MA, Senior Conservator-Restorer, and Kristina Matković, mag. art., MSU conservator-restorer.