Basel I is the term which refers to a round of deliberations by central bankers from around the world, and in 1988, the Basel Committee (BCBS) in Basel, Switzerland, published a set of minimal capital requirements for banks. This is also known as the 1988 Basel Accord, and was enforced by law in the Group of Ten (G-10) countries in 1992, with Japanese banks permitted an extended transition period. Basel I is now widely viewed as outmoded, and a more comprehensive set of guidelines, known as Basel II are in the process of implementation by several countries.

Background
The Committee was formed in response to the messy liquidation of a Frankfurt bank in 1974. On 26 June 1974, a number of banks had released Deutschmark to the Bank Herstatt in Frankfurt in exchange for dollar payments deliverable in New York. On account of differences in the time zones, there was a lag in the dollar payment to the counter-party banks, and during this gap, and before the dollar payments could be effected in New York, the Bank Herstatt was liquidated by German regulators.
This incident prompted the G-10 nations to form towards the end of 1974, the Basel Committee on Banking Supervision, under the auspices of the Bank of International Settlements (BIS) located in Basel, Switzerland.