- CTAO : Thomas A. O'Shaughnessy Papers
- CTAO Series : Thomas A. O'Shaughnessy Biographical Information
- CTAO 1/01 Folder : O'Shaughnessy's Membership and Business Cards 1926-1942
- CTAO 3/01 Folder : Thomas A. O'Shaughnessy Biographical and Family Information 1942-2002
- CTAO 1/02 Folder : O'Shaughnessy Family Tree 1980
- CTAO 1/03 Folder : Irish American Hall of Fame Nomination - Thomas A. O'Shaughnessy 2008
- CTAO 1/04 Folder : Article in New World on O'Shaughnessy's Life Play
- CTAO 1/05 Folder : Celtic Revived - The Artistry of Thomas O'Shaughnessy / by Timothy Barton
- CTAO 1/06 Folder : Photographs of Thomas A. O'Shaughnessy and Family (1 of 2)
- CTAO 4/07 Folder : Photographs of Thomas A. O'Shaughnessy and Family (2 of 2)
- CTAO Series : Thomas A. O'Shaughnessy Correspondence
- CTAO 1/07 Folder : Thomas O'Shaughnessy - letter to his brother Frank from Pueblo, Colorado 1892
- CTAO 1/08 Folder : Notes from Thomas A. O'Shaughnessy and letters from Aunt Mary 1909
- CTAO 1/09 Folder : Thomas A. O'Shaughnessy original letters and poems to and from 1915-1953
- CTAO 1/10 Folder : Thomas A. O'Shaughnessy original letters to and from 1916-1950
- CTAO 1/11 Folder : Letters from Edward Kemp, Acquisitions Librarian at University of Oregon regarding preservation of Thomas O'Shaughnessy collection 1965-1966
- CTAO 1/12 Folder : Correspondence 1980-2006
- CTAO 1/13 Folder : Letter from Nicola Gordon Bowe to Joe O'Shaughnessy regarding Thomas A. O'Shaughnessy's work 1988
- CTAO 1/14 Folder : Letter from Congressman, Frank Annunzio to Joe O'Shaughnessy regarding Columbus Day becoming a national holiday 1989
- CTAO 1/15 Folder : Conrad Schmitt Studios Inc. letters regarding the restoration of Old St. Patrick's stained glass windows 1992-2006
- CTAO 1/16 Folder : Correspondence and research from Ellen Skerrett regarding Thomas O'Shaughnessy and the Irish in America 1996-2005
- CTAO 1/17 Folder : Request to use Thomas O'Shaughnessy design from Ambrose University 1999
- CTAO 1/18 Folder : Letter to Joseph O'Shaughnessy to his father, Thomas O'Shaughnessy 1928/0528
- CTAO Series : Thomas A. O'Shaughnessy Projects
- CTAO Subseries : Columbus Day Pageant
- CTAO 1/19 Folder : Pageant Program of the Voyage and Landing of Columbus 1910-1911
- CTAO 1/20 Folder : Columbus Exposition original photos of the ships (photocopies) 1910-1911
- CTAO 1/21 Folder : Mayor of Chicago announcement on the annual Columbus pageant 1911
- CTAO 1/22 Folder : Columbus classic stamps reissued announcement 1992
- CTAO 1/23 Folder : Columbus inspired artwork and postcard
- CTAO 6/06 Folder : O'Shaughnessy poem and artwork design for Chicago Columbus pageant
- CTAO Subseries : Old St. Patrick's Church
- CTAO 4/02 Folder : Old St. Patrick's Church - Newspaper Clippings 1914-2008
- CTAO 1/24 Folder : The History of Old St. Patrick's by Terrence Martin Heeney 1990
- CTAO 1/25 Folder : Crossroads: Old St. Patrick's Church newsletter and articles pertaining to O'Shaughnessy and Renaissance Campaign 1993
- CTAO 1/26 Folder : Old St. Patrick's Church Programs and Handouts
- CTAO 1/27 Folder : Old St. Patrick's postcards
- CTAO 1/28 Folder : St. Patrick's Sunday Mass Advertisement artwork
- CTAO 1/29 Folder : St. Patrick's obstain from liquor pledge
- CTAO 1/30 Folder : Christopher Columbus Painting for St. Patrick's
- CTAO 1/31 Folder : McSwiney Memorial Window at St. Patrick's
- CTAO 1/32 Folder : St. Patrick's Church background information
- CTAO 3/02 Folder : Small sketches and painting ideas
- CTAO 1/33 Folder : Old St. Patrick's Photographs (Photocopies) (1 of 2)
- CTAO 7/02 Folder : Old St. Patrick's Photographs (2 of 2)
- CTAO 4/10 Folder : Old St. Patrick's Church Renaissance Campaign program
- CTAO 6/03 Folder : O'Shaughnessy program design for Old St. Patrick's
- CTAO Subseries : Cathedral of the Immaculate Conception
- CTAO 1/34 Folder : Diocesan Diamond Jubilee 1853-1928 and Cathedral Dedication 1928
- CTAO 1/35 Folder : Cathedral of the Immaculate Conception 2005-2007
- CTAO 1/36 Folder : Photographs (Photocopies) of the Cathedral of the Immaculate Conception in Springfield, Illinois 2007
- CTAO 1/37 Folder : Dedication Programs for the Cathedral of the Immaculate Conception, Renovated Church and New Altar 2009
- CTAO Subseries : Various Projects
- CTAO 4/01 Folder : The Shepard-Printer's Window 1914-1919
- CTAO 4/03 Folder : Installation Banquet Catholic Church Extension Society program and artwork 1916
- CTAO 4/04 Folder : The Irish Fellowship Club of Chicago programs and artwork 1921-1930
- CTAO 3/03 Folder : The Irish Fellowship Club of Chicago 1907-1988
- CTAO 3/04 Folder : St. Catherine's Church in New Jersey, 1921-2001 1921-2001
- CTAO 1/38 Folder : The Palette and Chisel Club of Chicago 1926, 2004
- CTAO 1/39 Folder : International Eucharistic Congress 1926
- CTAO 7/01 Folder : International Eucharistic Congress posters 1926
- CTAO 1/40 Folder : Stained Glass Windows at 145 Elks Place, New Orleans 1976
- CTAO 5/03 Folder : Sketches and Designs for The Elk's Place, New Orleans
- CTAO 1/41 Folder : Artist Guild Window at St. Stephen's Episcopal Church 1992
- CTAO 1/42 Folder : The Wesley Pentecost Window
- CTAO 1/43 Folder : Rose Window at St. Vincent de Paul
- CTAO 1/44 Folder : Century of Progress Host House
- CTAO Series : Thomas A. O'Shaughnessy - Artwork and Methods
- CTAO 2/01 Folder : O'Shaughnessy Glass Making Method Patents and Formulas 1914-1936
- CTAO 2/02 Folder : The Notre Dame Scholastic Vol. L. No. 35 Diamond Jubilee Number artwork by Thomas A. O'Shaughnessy 1917
- CTAO 2/03 Folder : The Gullible Gull - artwork by O'Shaughnessy 1935-1954
- CTAO 2/04 Folder : Irish Books in the Chicago Pubic Library Program - Cover artwork by O'Shaughnessy 1942
- CTAO 2/05 Folder : Christmas cards, birth announcements, and other card designs by Thomas A. O'Shaughnessy 1950-1951
- CTAO 3/05 Folder : O'Shaughnessy sketchbooks (1 of 2) c1940-1950
- CTAO 3/06 Folder : O'Shaughnessy sketchbooks (2 of 2) c1940-1950
- CTAO 3/07 Folder : 'His Book' - O'shaughnessy design
- CTAO 3/08 Folder : Sketches, designs and artwork
- CTAO 2/06 Folder : Various sketches and small nature paintings (1 of 2)
- CTAO 2/07 Folder : Various sketches and small nature paintings (2 of 2)
- CTAO 2/08 Folder : Untitled religious sketches by O'Shaughnessy
- CTAO 2/09 Folder : Untitled Buffalo ink drawing by O'Shaughnessy
- CTAO 3/09 Folder : Drawings and paintings of stained glass windows by O'Shaughnessy
- CTAO 2/10 Folder : Illinois Chapter American Irish historical society - DePaul University Chicago artwork design
- CTAO 2/11 Folder : "A Drink Comes Before a Story" illustration
- CTAO 2/12 Folder : O'Shaughnessy design for the Missionary Servants of the Most Blessed Trinity
- CTAO 2/13 Folder : Paul Preaching at Athens booklet designed by O'Shaughnessy for "The New World" Church Goods Store
- CTAO 4/05 Folder : Untitled Birth Announcement drawings
- CTAO 4/06 Folder : O'Shaughnessy Trace paper sketches
- CTAO 4/08 Folder : O'Shaughnessy untitled watercolor
- CTAO 4/09 Folder : O'Shaughnessy Designs (1 of 2)
- CTAO 6/02 Folder : O'Shaughnessy Designs (2 of 2)
- CTAO 5/04 Folder : St. Coleman - artwork
- CTAO 5/05 Folder : O'Shaughnessy untitled nature painting
- CTAO 5/06 Folder : O'Shaughnessy untitled sketch
- CTAO 6/04 Folder : O'Shaughnessy game board design
- CTAO 6/05 Folder : O'Shaghnessy illustration, "Christmas, Chicago, 1674," undated
- CTAO 6/07 Folder : O'Shaughnessy untitled paintings
- CTAO 6/08 Folder : O'Shaughnessy untitled crest artwork
- CTAO 6/09 Folder : O'Shaughnessy untitled religious design