The Combined Defence Services Examination (II) – 2011 is a national-level entrance test for Indian students aiming to join the Indian Military Academy, Naval Academy, Air Force Academy, or Officers' Training Academy. Conducted by the Union Public Service Commission, it assesses candidates' aptitude and subject knowledge for admission to defence training academies. The examination tests English, general knowledge, and elementary mathematics, with eligibility based on academic qualifications and age limits.

Indian citizens who are graduates or final-year degree students can apply. For the Indian Military Academy and Officers' Training Academy, a recognised degree is required. The Naval Academy requires a B.Sc. with Physics and Mathematics or a Bachelor of Engineering. The Air Force Academy needs a degree with Physics and Mathematics at the 10+2 level or a Bachelor of Engineering. Age limits vary by academy, typically between 19 and 24 years.

Candidates must apply online through the official UPSC portal. The application involves registration, filling the form, uploading documents, and paying the fee. Admit cards are issued to eligible applicants. The examination is held at designated centres across India. Detailed instructions are provided in the official notification.