Roulston has applied for the post left vacant by Steve Martin, whose four-year tenure ended last month.
"I feel the time is right for me to again be a head coach and take on this exciting and very challenging position," Roulston said in his application.
"I know I have the knowledge, experience and ability required to be successful in this role."
Roulston has had limited experience as a head coach, but his resume is stacked with coaching and development jobs.
His most recent and high-profile roles were at Super 14 level, where he was a Highlanders assistant in 2008 and a Hurricanes assistant from 2003 to 2007.
Roulston has also had experience with a range of teams in Mid Canterbury, Wanganui, Japan and Romania.
The New Zealand Rugby Union advertised Roulston's Highlanders assistant coaching job late last year and appointed rising Hawkes Bay coach Peter Russell in his place.
Roulston was previously on the Otago Rugby Football Union payroll as its development officer (1995-97), director of coaching (1998-2001) and academy director (1999-2001).
Applications for the Otago coaching role close on November 20.
The early favourite is Otago Country coach and former long-serving player David Latta.
