IMPORTANT NOTICE
April Preliminary Market and GMC Invoices Available

Preliminary invoices for the month of April were sent to Market Participants
on Friday 6/22/01 for your review.

Please open your EDI mailbox to retrieve them if you have not done so
already.

As a reminder, payments (market payments due-ISO and GMC) for the April
preliminary invoices will be due at the ISO no later than 10:00 a.m. PST on
Friday, June 29, 2001.  The ISO will transmit market payments due-SCs based
on collections from SCs as soon thereafter as practicable.

Please remember how critical it is for the ISO to receive all payments by
10:00 a.m. PST on the due date and the importance of using the correct
account number which appears on each invoice.

Client Relations Communication
CRCommunications@caiso.com