The UPSC Civil Services Examination is conducted in two successive stages: Preliminary Examination (objective type) for screening candidates, and Main Examination (written and interview) for final selection. The Prelims consists of two papers carrying 400 marks total, serving only as a screening test. Qualified candidates (about 12-13 times the total vacancies) proceed to Mains. The Main Examination includes 9 papers of conventional essay type, with interview carrying 275 marks. Final ranking is determined by Mains performance.