[citation needed] In 1977, Pádraigín was the first woman to read the news headlines in Irish at RTÉ, Ireland's national broadcaster.

[citation needed] She left RTÉ in 1980 to study for a master's degree in the University of Ulster and in 1984 began teaching in Dundalk, County Louth.

Her composition Don't give me the whole truth (Ná tar le hIomlán na Fírinne) is featured on Davies' 2002 album, Open The Door Softly.

The song Éalaigh Liom (Elope with Me) was performed on BBC Two's Highland Sessions programme presented by Mary Ann Kennedy.

Her book, A Hidden Ulster: People, songs and traditions of Oriel was published 2004 by Four Courts Press, and later republished on Ceoltaí Oirialla.

A Hidden Ulster is a 540-page collection of rare songs, their histories, biographies of authors, collectors and scribes, and documentation of folk traditions in Oriel from the 17th century onwards.

Collaborators Palle Mikkelborg, Helen Davies and featured Ní Uallacháin's composition from the album, An Leannán (The Beloved) on Masters of the Irish Harp in 2011.

As traditional singer in residence at the Seamus Heaney Centre for Poetry at Queen's University Belfast, Pádraigín collaborated with Colmcille and ULTACH Trust in creating series of events based around the exhibition of An Leabhar Mór (The Great Book of Gaelic), which was being exhibited in the Ulster Museum between October and November 2005.

[12] In November 2011, Pádraigín released her first album on the Ceoltaí Éireann label, Songs of the Scribe with early Irish lyrics and translations set to her new compositions and accompanied by harpist Helen Davies.

She received the Outstanding Contribution to Traditional Music award and performed ‘Séamus Mac Murfaidh’ (with her local protégés, Blaithín Mhic Cana and Piaras Ó Lorcáin), and her own composition, ‘Gleann na nDeor’ (with The Voice Squad) at the ceremony.

In 2019 a second documentary on her work was broadcast on TG4, "Sé Mo Laoch" In 2022, she contributed a keening song to the soundtrack of John Connors' film The Black Guelph, which details the generational abuse suffered by Irish travellers at the hands of the state and church.

The album also sees Ní Uallacháin collaborate again with guitarist Steve Vai on the title track, and with Indian classical flautist Rajat Prasanna.

Ní Uallacháin has collaborated throughout her career, particularly with Garry Ó Biain, Steve Cooney, Dónal O'Connor, Helen Davies and Máire Breatnach.

Pádraigín's song compositions have been recorded by Dolores Keane, Muireann Nic Amhlaoibh, Danú, The Black Family, Eithne Ní Uallacháin, Len Graham, Skylark, Mairéad Ní Mhaonaigh, Altan, Steve Vai, Nuala Kennedy, Cathie Ryan and Hal Leonard Concert Band.