1. The UPSC civil services exam consists of three stages - a preliminary exam, main exam, and personality test (interview). 2. The preliminary exam has two objective papers testing general studies and an aptitude test. Candidates who pass this move to the main exam. 3. The main exam has 9 papers, including two qualifying papers on English and an Indian language. The remaining 7 papers test general studies, an essay, and an optional subject. Candidates are ranked based on the marks of these 7 papers. 4. The personality test involves an interview with a panel to assess the candidate's mental and emotional aptitude and knowledge. The interview carries significant weightage.