How IWC works
The IWC has two major meeting forums, the Commission Meeting and the Scientific Committee Meeting. Each meeting is approximately two weeks in length. The Scientific Committee Meeting is attended by up to 200 scientists, and the Commission Meeting is attended by around 400 people including government delegates, observers from non-member governments, other inter-governmental organisations, non-government organisations (NGOs) and representatives of the media. Private individuals are not able to attend.
In 2012, the Commission agreed to move from annual to biennial Commission Meetings. The Scientific Committee continues to meet annually. In years where both meetings are held, a period of at least 100 days separates the two. This is to allow time to read and digest the reports of the Scientific Committee Meeting, before the Commission Meeting begins.
In recognition of the extended periods between Commission meetings, a new Bureau has been created, comprising eight Commissioners. The Bureau comes together bi-annually to ensure implementation of the Commission’s workplan.
The location of meetings is decided either through invitation from a member government, or in the absence of an invitation it is usually held in the United Kingdom where the Secretariat is based.
(Extracted from the IWC web site)