The international banking accord first published in 1988 that set capital requirements was Basel I, also called the 1988 Basel Accord.
Basel I was issued by the Basel Committee on Banking Supervision, a forum of central banks and banking supervisors headquartered at the Bank for International Settlements in Basel, Switzerland. Its central goal was to make banks hold capital proportionate to the credit risk of their assets.
The accord introduced a minimum risk-weighted capital ratio of 8 percent, with capital divided into tiers reflecting its quality and loss-absorbing ability. The framework initially focused mainly on credit risk and was adopted progressively by the Group of Ten countries and other jurisdictions.
Basel I is the first in a sequence, not the latest standard. Basel II expanded risk measurement and supervisory review, while Basel III followed the 2007–09 financial crisis with stronger capital, leverage, liquidity, and conservation-buffer requirements. Solvency II is a separate European Union regulatory regime for insurers, not banks.