[2] In a career that has attracted both accolades and controversy,[1] Gallagher has owned restaurants in Dublin, New York, London, Las Vegas and Cape Town, and has featured in two reality television cooking series.

[1] In February 2021, Gallagher opened "Off the Menu Food Emporium", a delicatessen, coffee and wine shop serving tapas-style meals, in Port Elizabeth, South Africa.

In his autobiography Back on the Menu: My Rollercoaster Life, he revealed how the kitchen was home to him as a child and how he disliked school because of the abuse he received at both institutions.

[4] Inspired by the cooking of his mother and his grandmother, he left St Eunan's at the age of 16 and began training as a chef at Killybegs Catering College.

[1] While he was offered career launching positions in Ireland, he determined he should go to New York City to further pursue his dream of becoming a world class chef.

[2][7] He left Ireland to return to New York City, where he married an American citizen and opened a bar, Traffic, at First Avenue and 50th Street in Manhattan.

[9] The original contract was furnished stating Gallagher owned the three paintings and the jury returned a 'not guilty' verdict less than two hours after it started deliberations.

[13] Geisha Wok and Noodle Bar stopped trading in August 2009 when Gallagher decided to move back to Ireland and open Salon Des Saveurs.

[14] After planning to return to Ireland during Summer 2009[15] to open a new Irish restaurant, Gallagher and his second wife, former Miss Port Elizabeth finalist Candice Coetzee, and their two sons, moved to Dublin.

He has headlined two reality television series – Conrad’s Kitchen: Access All Areas[31] on BBC Food in 2005, and Head Chef on Irish national broadcaster RTÉ's TV3 in 2011.