• promote the learning and use of modern languages;
• improve the status of all professional linguists;
• establish and maintain high standards of work;
• serve the interests of all linguists; and
• ensure professional standards amongst language practitioners through its Code of Conduct.

Through the IoL Educational Trust, a UK-accredited examining body, and Language Services Limited, it currently offers examinations and assessments in over 100 languages.

The Hong Kong Society (HKS) of CIOL was established in 1984. It is committed to promoting professional language use in Hong Kong. It organizes professional development functions for local members, and publishes a newsletter and an academic journal.

HKS welcomes birds of the same feather joining it as members. On admission, Fellows, Members and Associates of CIOL may become voting members and all others may apply to HKS for non-voting membership. Basically the rights and privileges of voting and non-voting members are the same except that voting members can vote at General Meetings of HKS and can hold office on its Executive Committee.

CIOL qualifications are internationally recognized. For example, using the MCIL qualification, a large number of members in Hong Kong have successfully entered postgraduate study programmes in local and overseas universities. The Civil Service Bureau of the Hong Kong SAR Government and its subvented bodies have also considered MCILs, on the basis of the Final Diploma in English and Chinese or International Diploma in Bilingual Communication , favourably for certain degree-entry civil service grades in specialized fields for which language skills in English are one of the requirements. The Diploma in Translation (DipTrans) is a popular international CIOL examination. DipTrans is recognized to be a qualification at master’s degree level. Members of the public may apply to the Hong Kong Examinations and Assessment Authority to sit for the examinations.