The news caused some concern and displeasure from the Steam community due to the lack of any public farewell or notification regarding Bailey's departure. On Valve's official website circa 2010, his function was described as follows: 'Kelly is Valve's senior audio producer, responsible for creating sound effects & music.' Īround March 2011, Kelly Bailey left Valve with colleague Mike Dussault to work on their project Sunspark Labs LLC, launched in December 2010, developing iOS applications, their first being 'Morfo', released in June 2011. In addition to composing the soundtrack for Half-Life 2, Bailey was one of four Valve employees - the others being David Speyrer, Eric Kirchmer, and Greg Coomer - who served as facial models for Gordon Freeman's face in the game's promotional materials.

He created all the music and sound effects for Half-Life.'

On Valve's official website circa 1998, his function was described as follows: 'Kelly, formerly a product unit manager at Microsoft, has a programming background that includes consumer multimedia, database engines, and networking. On the defunct Half-Life website, his function was described as follows: 'Kelly did all of the music and sound effects for Half-Life, and wrote sound code to create character speech and DSP reverb effects.'