The Directorate of Ordnance (Coordination & Services) (abbreviated: DOO(C&S)) is an authority under the Department of Defence Production (DDP) of Ministry of Defence (MoD), Government of India. Its primary work is to management, give instructions and make coordination of government ordnance production public companies. It is the main regulatory body of Indian Ordnance and its administration civil service, Indian Ordnance Factories Service (IOFS). The DOO(C&S) earlier known as Ordnance Factory Board (OFB), consisting of the Indian Ordnance Factories. In 2021, Government having corporatise the functions of the 41 Indian Ordnance Factories into 7 Defence Public Sector Undertakings (DPSUs), the Government is merging them again in 2024, as the output of one factory serves as the input of the other.
OFB was the 37th-largest defence equipment manufacturer in the world, 2nd-largest in Asia, and the largest in India. OFB was the world's largest government-operated production organisation, and the oldest organisation in India. It had a total workforce of about 80,000. It was often called the "Fourth Arm of Defence", and the "Force Behind the Armed Forces" of India. Its total sales were at US$3 billion (₹22,389.22 crores) in the year 2020–'21.
It was engaged in research, development, production, testing, marketing and logistics of a product range in the areas of air, land and sea systems. OFB consisted of forty-one ordnance factories, nine training institutes, three regional marketing centres and four regional controllerates of safety, which are spread all across the country. Every year, 18 March is celebrated as the Ordnance Factory Day in India.