The Second Review Conference (1986) agreed to the exchange of Confidence-building Measures (CBMs) “in order to prevent or reduce the occurrence of ambiguities, doubts and suspicions and in order to improve international cooperation in the field of peaceful biological activities”. The CBMs were expanded during a meeting of scientific and technical experts in 1987, and were modified and considerably expanded by the Third Review Conference in 1991. These forms were used for twenty years between 1991 and 2011.

The Sixth Review Conference in 2006 agreed on several improvements to the mechanisms for submission and distribution, notably on the development of a mechanism for the electronic submission and distribution of CBMs. Paper publication of CBM submissions was subsequently discontinued. The Seventh Review Conference in 2011 revised the CBMs as well as the relevant modalities and forms.

As a result of this process, the CBMs now consist of six measures, A to G (without D):

CBM A Part 1: Exchange of data on research centres and laboratories;
Part 2: Exchange of information on national biological defence research and development programmes.
CBM B Exchange of information on outbreaks of infectious diseases and similar occurrences caused by toxins.
CBM C Encouragement of publication of results and promotion of use of knowledge.
CBM E Declaration of legislation, regulations and other measures.
CBM F Declaration of past activities in offensive and/or defensive biological research and development programmes.
CBM G Declaration of vaccine production facilities.

CBMs are to be submitted the BWC Implementation Support Unit in the Geneva Branch of United Nations Office for Disarmament Affairs no later than 15 April each year. The information provided covers the previous calendar year (for example, you should submit your CBM covering calendar year 2010 no later than 15 April 2011).