S. Asgeirsdottir studied at the Reykjavik Art College 1976-78 and at Edinburgh Collage of Art 1979-84 where she graduated with a B.A. honours degree in 1983 and a post-graduate diploma 1984.

She has participated in numerous group exhibitions in Iceland and abroad. Her works are in various private collections in Europe, Japan and New Zealand, and she has executed numerous commissions for private houses in Iceland, England and Scotland.

Her commissions in public places in Iceland include the Nordic House Reykjavik, National and University Library of Iceland, Landsbankinn Headquarters, Glitnir Bank Laekjargata, the hospital chapels in Vestmannaeyjar and Isafjordur, Reykjavik Harbour Headquarters, Husavik Primary School and Langholtskirkja Reykjavik.

In addition to her architectural stained glass, she makes walls of glass reliefs (her black pieces), paints, works in paper, artist-books, book covers and book illustrations, posters and logos.