In 1975 Ruggiero, along with drummer Giancarlo Colzi and three former members of Jet (keyboardist Piero Cassano, bassist Aldo Stellita and guitarist Carlo Marrale) formed Matia Bazar.

They won the 1978 Sanremo Music Festival] with "... e dirsi ciao" and represented Italy at the Eurovision Song Contest 1979 with "Raggio di luna".

[2] Other popular hits by the band include "Ma perché", "Solo tu", "Per un'ora d’amore", "Stasera che sera", "Cavallo bianco", "Il video sono io", "Mister Mandarino", "Souvenir", "Ti sento" and "Vacanze romane".

The song, written together with her husband Roberto Colombo, was dedicated to Ruggiero's former bandmate in Matia Bazar Aldo Stellita, who had died prematurely the year before.

Ruggiero's third solo album, Sospesa, featured Ennio Morricone, who contributed to "And Will You Love Me", and Giovanni Lindo Ferretti, who co-wrote "Di perle e inverni".

On 4 June 2004 she performed a concert at the Brooklyn Museum in New York as a worldwide preview of her new album Sacrarmonia Live (Il viaggio).

The album, a collection of religious and spiritual songs from different parts of the world, was previwed in Europe on 25 November 2004 with a gig at The Sugar Club in Dublin.

In October 2009, the German dance act Scooter released a cover version of "Ti sento", featuring Ruggiero on vocals.

On June 18, 2015, she collaborated with ConiglioViola on "Requiem Elettronico", a collection of ten Italian pop songs focused on the theme of death.

On November 25, 2016, Ruggiero released "La vita imprevedibile delle canzoni", an album recorded at Fazioli Pianoforti factory in Sacile.