In the 2000s, Rudolf Stingel's art continued to engage deeply with the conceptual and material possibilities of painting, while also exploring the nature of artistic creation and audience interaction in innovative ways. His work during this period is marked by several key themes and methods, including the use of industrial materials, the exploration of photography, and the creation of immersive, participatory installations. Stingel is known for his installations that transformed spaces and invited audience interaction, such as the use of Celotex insulation boards that he covered gallery walls with. These installations were seen in significant exhibitions, including the 2003 Venice Biennale and his 2007 mid-career retrospective at the Museum of Contemporary Art, Chicago, and the Whitney Museum of American Art in New York. Visitors were encouraged to inscribe, puncture, or otherwise mark the reflective surfaces, creating collaborative, ever-evolving artworks that challenged traditional notions of artistic authorship and the sanctity of the art object​ (Wikipedia)​. During this era, Stingel also delved into photorealism, creating series of paintings based on photographs, including self-portraits that explored identity, memory, and the passage of time. This phase represented a significant shift in his work, moving from abstract and conceptual installations to more traditional forms of representation, albeit through a highly conceptual lens. The self-portraits, based on photographs by other photographers, such as Sam Samore, were executed in a grayscale palette, underscoring the mediated nature of personal and historical memory​ (Wikipedia)​. Stingel's innovative approach extended to the transformation of his earlier interactive installations into new works of art. For instance, his 2007 installations' marked Celotex panels were later exhibited as gilded paintings, transmuting the ephemeral marks of audience interaction into precious objects. These works, shown in his first solo exhibition at Gagosian Gallery's Hong Kong outpost in 2015, encapsulate his interest in the themes of transformation and value, the interplay between the ephemeral and the eternal, and the participatory role of the audience in the creation of art​ (Art Asia Pacific)​. Stingel's first solo museum exhibition in the United States, held at the Whitney Museum of American Art in 2007, offered a comprehensive survey of his career to that point. It highlighted his innovative use of materials such as rubber, carpet, painted aluminum, and Styrofoam, alongside traditional paint. This exhibition underscored his contributions to ongoing conversations about the essence of painting, including questions of authenticity, hierarchy, meaning, and context​ (Whitney Museum of American Art)​. Through these diverse practices, Rudolf Stingel's work in the 2000s solidified his reputation as an artist who continually challenges and redefines the boundaries of contemporary painting and installation art. His explorations of materiality, participation, and the conceptual underpinnings of art production and reception have had a lasting impact on contemporary art discourse.