[1] Aarnio joined the American Institute of Architects New York Chapter in 1948 and established his own firm that year.
[3] He was also the chairman of the Arts and Architecture committee of the Finlandia Foundation from 1960; the vice chairman of the Zoning Board of Appeals, River Edge, New Jersey, from 1965; architectural consultant for the American-Scandinavian Foundation Scholarship Awards Committee from 1965; and liaison as the planning board of River Edge, New Jersey, from 1969.
[1] Aarnio received a Citation for Excellence for the U.S. Exhibition in Sweden, Poland and Greece, Veterans of Foreign Wars in 1959.
He was published in numerous articles, which featured contributions on architecture and design in books and magazines.
[1] He was a member of the Board of Trustees for the Scandinavian Seminar for University Level Studies in Scandinavia from 1959.