- The Cabinet Secretariat and PMO are distinct bodies supporting the Prime Minister. - The Cabinet Secretariat provides secretarial support to the Cabinet and administers rules of business. - The PMO assists the Prime Minister in various functions. - The Office of the Principal Scientific Adviser is under the Cabinet Secretariat. - DBT Mission coordination is often overseen by the Cabinet Secretariat. - DARPG and DoPT are part of the Ministry of Personnel, Public Grievances and Pensions, not the PMO or Cabinet Secretariat.