Biological Weapons Convention (BWC)

The Biological Weapons Convention (BWC) is a binding international disarmament and non-proliferation treaty with the objective to outlaw biological weapons.

What are biological weapons?

The term biological weapons covers bacteriological and toxin weapons that use microbiological and other biological toxins and agents for hostile purposes or armed conflict. Biological weapons are considered weapons of mass destruction and are outlawed under international law by the BWC.


The Convention prohibits the development, production, stockpiling and transfer of biological weapons and requires members to destroy any stockpiles or use them for peaceful purposes.


The BWC entered into force in 1975 and has 183 Member States. The ban on the use of biological weapons implicit in the BWC was already enshrined in international law in the Geneva Protocol of 1925.

The BWC does not have a binding verification system. Instead, the States Parties have agreed on non-legally binding confidence building measures (CBMs), which require annual reporting on, among other things, relevant research facilities, laboratories, legislation, and human vaccine production facilities. To date, attempts to negotiate an additional protocol on a verification regime have failed. The Australia Group, whose 42 participating States are also parties to the BWC, supports implementation of the BWC non-proliferation obligation through internationally harmonized export controls.

The BWC Member States meet annually for a Meeting of Experts and a Meeting of States Parties. Every five years (most recently in 2016), the Meeting of States Parties takes the form of a Review Conference. The BWC and its States Parties are assisted in the implementation of the Convention and, in particular, the CBMs by the Implementation Support Unit (ISU). The ISU is established within the Geneva Branch of the United Nations Office for Disarmament Affairs and publishes an annual report on its activities.

BWC Member States

Karte BWÜ_klein

BWC Key Info

  • Entry into force: 1975
  • Entry into force in Switzerland: 1975
  • Members: 183

Last modification 09.09.2021

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