As agreed by the participating States at the Third Follow-up Meeting (1986-89), the next stage of the negotiations on Confidence- and Security-Building Measures (CSBMs) began in Vienna on 9 March 1989.

These talks took place in parallel with the negotiations on Conventional Armed Forces in Europe (CFE) between the participating States that were members of NATO or the Warsaw Pact.

Exchanges of military information

As a first step, the discussions on CSBMs resulted in the Vienna Document 1990 (17 November). This broadened the scope of mutual information exchange, including an obligation to provide the following information on an annual basis:

• Existing military forces.
• Planned deployments of major weapons systems.
• Military budgets.

It also widened the scope of verification measures, and introduced an Annual Implementation Assessment Meeting, which would "discuss the present and future implementation of agreed CSBMs."

The Vienna Document 1990 was later amended in the Vienna Document 1992, which, inter alia, made further provisions for annual exchanges of military information.

Treaty on Conventional Armed Forces in Europe

Meanwhile, as a result of the parallel CFE talks, the Treaty on Conventional Armed Forces in Europe was signed by 22 participating States in Paris on 19 November 1990.

This legally-binding treaty was a complex instrument aimed at establishing a military equilibrium at a lower level between the 22 NATO and Warsaw Pact states by providing ceilings on the number of military vehicles and aircraft each side could have.