The object of the Association is to bring into closer union and friendship, all former students of Campion Hr. Sec. School and to foster and perpetuate their interest and connection with their "Alma Mater" and also to assist the old boys in any way within the powers of the Association.

The birth of Campion Old Boy's Association could be traced back to the 13th School Day n 1946. The Principal during that period, Fr. Hession, had accepted the suggestion of Fr.Shields and expressed the need for an alumini association. So the same year on December 1st, the feast of Blessed Edmund Campion, the Campion Old Boys', Association was founded with Fr.Shields as the President and Mr.Joseph Rodrigues as the Secretary. The first reunion day of the association was held on the 31st July 1946, on the feast of St.Ignatius of Loyola. In 1948, Rev.Fr.Shields left for Malta and Rev.Fr.Merrifield took over as the President of the Association. He was to become the longest serving President from 1948 to 1972 for a record period of 25 years.

The Silver Jubilee of COBA was celebrated on 19th September 1971. The year 1972 was the Golden Jubilee of Fr.Merrifield. The Reunion Day that year was held on 8th October, the President's 74th birthday. It was a great day for the many OBs who attended, for apart from the usual celebrations, a special function in the evening under the Chairmanship of Fr.Tamby felicitating Fr.Merrifield, was held. The same year the Jesuits were to leave Campion and the school was to be handed back to its owner, the Bishop of Trichy.

The Golden Jubilee of COBA was celebrated on the 27th and 28th, December 1997. Today in the new millennium, COBA as an association continues to grow, especially with the infusion of a lot of young blood, bubbling with enthusiasm and being spontaneous in their efforts for the growth of the Association.