The UPSC Selection process happens in 3 stages: Civil Services (Preliminary) Examinations (Objective Type) and Civil Services (Main) Examination (Written) and Interview (Personality Test)
The examination consists of
Officially called the "Personality Test", the objective of the interview is to assess the personal suitability of the candidate for a career in public service by a board of competent and unbiased observers. The test is intended to evaluate the mental calibre of a candidate. In broad terms, this is really an assessment of not only a candidate's intellectual qualities, but also social traits and interest in current affairs. Some of the qualities to be judged are mental alertness, critical powers of assimilation, clear and logical exposition, balance of judgement, variety and depth of interest, ability for social cohesion and leadership, and intellectual and moral integrity.
The technique of the interview is not that of a strict cross-examination, but of a natural, though directed and purposive conversation that is intended to reveal the mental qualities of the candidate.
The interview is not intended to be a test either of the specialised or general knowledge of the candidate, which has been already tested through written papers. Candidates are expected to have taken an intelligent interest not only in their special subjects of academic study, but also in the events which are happening around them both within and outside their own state or country as well as in modern currents of thought and in new discoveries which should rouse the curiosity of all well-educated youth.