UPSC Civil Services IAS mains 2016: The Union Public Service Commission (UPSC) is all set to conduct the mains round for the Civil Services recruitment exam for the Indian Administrative Services (IAS) posts on December 3 this year. The recruitment drive goes through two stages: the prelims and the mains round. The prelims round has already been conducted for which the result has been released. Candidates who clear the prelims round have to fill up the DAF form for applying to the mains round. Those who clear the mains are then called for an interview.