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                          N E W S   R E L E A S E

             TRANSCANADA CORPORATION ARRANGEMENT EFFECTIVE TODAY

CALGARY, Alberta - May 15, 2003 - (TSX: TRP) (NYSE: TRP) - TransCanada
Corporation announced that the plan of arrangement to establish it as the
parent company of TransCanada PipeLines Limited has received all necessary
regulatory approvals and certificates making it effective today.

As of today, common shareholders of TransCanada PipeLines Limited have
automatically become common shareholders of TransCanada Corporation.  Each
TransCanada PipeLines Limited common share is recognized as one TransCanada
Corporation common share.  TransCanada Corporation common shares are now
publicly traded on the Toronto and New York stock exchanges under the symbol
"TRP", the symbol historically used by TransCanada PipeLines Limited.
Preferred shares in TransCanada PipeLines Limited are publicly traded under
the new symbol "TCA".

The establishment of TransCanada Corporation will have no impact on
TransCanada PipeLines Limited's day to day operations, services or
obligations.  The assets and liabilities of TransCanada PipeLines Limited
remain with TransCanada PipeLines Limited.  Debt holders and preferred
shareholders of TransCanada PipeLines Limited continue to hold these
securities in this company.  TransCanada Corporation owns all of the
outstanding common shares of TransCanada PipeLines Limited.

TransCanada is a leading North American energy company.  We are focused on
natural gas transmission and power services with employees who are expert in
these businesses.  Our network of approximately 38,000 kilometres of pipeline
transports the majority of Western Canada's natural gas production to the
fastest growing markets in Canada and the United States.  TransCanada has
interests in more than 4,000
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megawatts of power - an equal amount of power can meet the needs of about
four million average households.  Our common shares trade under the symbol
TRP on the Toronto and New York stock exchanges.  Visit us on the internet at
www.transcanada.com for more information.

FORWARD LOOKING INFORMATION

CERTAIN INFORMATION IN THIS NEWS RELEASE IS FORWARD-LOOKING AND IS SUBJECT
TO IMPORTANT RISKS AND UNCERTAINTIES.  THE RESULTS OR EVENTS PREDICTED IN
THIS INFORMATION MAY DIFFER FROM ACTUAL RESULTS OR EVENTS.  FACTORS WHICH
COULD CAUSE ACTUAL RESULTS OR EVENTS TO DIFFER MATERIALLY FROM CURRENT
EXPECTATIONS INCLUDE, AMONG OTHER THINGS, THE ABILITY OF TRANSCANADA TO
SUCCESSFULLY IMPLEMENT ITS STRATEGIC INITIATIVES AND WHETHER SUCH STRATEGIC
INITIATIVES WILL YIELD THE EXPECTED BENEFITS, THE AVAILABILITY AND PRICE OF
ENERGY COMMODITIES, REGULATORY DECISIONS, COMPETITIVE FACTORS IN THE
PIPELINE AND POWER INDUSTRY SECTORS, AND THE CURRENT ECONOMIC CONDITIONS IN
NORTH AMERICA.  FOR ADDITIONAL INFORMATION ON THESE AND OTHER FACTORS, SEE
THE REPORTS FILED BY TRANSCANADA WITH CANADIAN SECURITIES REGULATORS AND
WITH THE UNITED STATES SECURITIES AND EXCHANGE COMMISSION.  TRANSCANADA
DISCLAIMS ANY INTENTION OR OBLIGATION TO UPDATE OR REVISE ANY FORWARD-
LOOKING STATEMENTS, WHETHER AS A RESULT OF NEW INFORMATION, FUTURE EVENTS
OR OTHERWISE.

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Media Inquiries:                     Glenn Herchak/Hejdi Feick
        (403) 920-7877

Investor & Analyst Inquiries:        David Moneta/Debbie Persad
        (403) 920-7911