International Standby Practices, International Chamber of Commerce Publication No. 590 (1998). ISP98 is one of the two most common sets of industry rules applicable to letters of credit (the other being Uniform Customs and Practice for Documentary Credits, International Chamber of Commerce Publication No. 600 (2007 Revision) (UCP 600)). ISP98 became effective on January 1, 1999 and was designed specifically for standby letters of credit. If a standby letter of credit (or a loan agreement under which letters of credit are issued) provides that ISP98 applies, the rules address procedural and interpretive matters relating to the letter(s) of credit that are not specifically covered in the letter(s) of credit (or the loan agreement). Where there is a governing loan agreement, the significance of ISP98 is lessened because the loan agreement and the letters of credit together typically address all aspects about drawings, amendments, expiration, and renewals of letters of credit.