Charles has occasionally intervened in projects that employ architectural styles such as modernism and functionalism. In 2009, Charles wrote to the Qatari royal family, the developers of the Chelsea Barracks site, labelling Lord Rogers's design for the site "unsuitable". Subsequently, Rogers was removed from the project and The Prince's Foundation for the Built Environment was appointed to propose an alternative. Rogers claimed the Prince had also intervened to block his designs for the Royal Opera House and Paternoster Square, and condemned Charles's actions as "an abuse of power" and "unconstitutional". Lord Foster, Zaha Hadid, Jacques Herzog, Jean Nouvel, Renzo Piano, and Frank Gehry, among others, wrote a letter to "The Sunday Times" complaining that the Prince's "private comments" and "behind-the-scenes lobbying" subverted the "open and democratic planning process". Piers Gough and other architects condemned Charles's views as "elitist" in a letter encouraging colleagues to boycott a speech given by Charles to RIBA in 2009.