For three years in the late 1890s he leased one of the studios in Pembroke Studios in Kensington, London, where he certainly painted portraits of Donald Smith, 1st Baron Strathcona and Mount Royal, and Lord Mount Stephen who were business associates of James J. Hill, of whom he made an etching in London in 1898 which was distributed to Hill's family and colleagues. According to a letter he wrote to Hill he started the portrait of Consuelo Yznaga, the 8th Duchess of Manchester, in London in 1898, but it is not known if it was ever completed. In 1903 he was one of a group of artists who invested in a new studio building, the Atelier Building, 33 West 67th Street. Muller-Ury lived in the top floor right studio, and incorporated a stained glass panel of the Müller coat-of-arms into the window (removed in 1947 and now at the Haus Müller in Hospental, Switzerland). The floors were all inlaid with borders of intarsia, and the smaller windows given mullions. He moved into the studio in 1904 and remained there until 1947.