Calgary, AB., Dec. 5, 2007 (TSX – COS.UN) — Canadian Oil Sands Trust (the “Trust” or “Canadian Oil Sands” or “we”) today announced that Syncrude had a fire in part of its Coker 8-3 in the flue gas section of the unit late in the day on December 4/early morning of December 5.  The fire has been extinguished.  At this time, further investigation is being undertaken by Syncrude as to the scope of damage and the cause of the fire.  It is expected that this investigation will take several days.  Production from Coker 8-3 is continuing at minimum rates.  At the current time, Canadian Oil Sands is unable to advise as to the extent of this reduced production and will provide more information when Syncrude is able to advise as to the extent of the damage.

Located near Fort McMurray, Alberta, Syncrude Canada operates large oil-sands mines and an upgrading facility that produces a light, sweet crude oil on behalf of its joint venture owners, which include Canadian Oil Sands Limited, ConocoPhillips Oilsands Partnership II, Imperial Oil Resources, Mocal Energy Limited, Murphy Oil Company Ltd., Nexen Oil Sands Partnership, and Petro-Canada Oil and Gas.

Canadian Oil Sands provides a pure investment opportunity in the Syncrude Project through its 36.74 per cent working interest.  The Trust is an open-ended investment trust managed by Canadian Oil Sands Limited and has approximately 479.3 million units outstanding, trading on the Toronto Stock Exchange under the symbol COS.UN.

Advisory: in the interest of providing Canadian Oil Sands Trust (“Canadian Oil Sands” or the “Trust”) unitholders and potential investors with information regarding the Trust, including management’s assessment of the extent of damage or impact of the fire on Syncrude’s operations and any impact on the Trust.  By their nature, forward-looking statements involve numerous assumptions, known and unknown risks and uncertainties, both general and specific, that contribute to the possibility that the predictions, forecasts, projections and other forward-looking statements will not occur.  Although the Trust believes that the expectations represented by such forward-looking statements are reasonable, there can be no assurance that such expectations will prove to be correct.  Some of the risks and other factors which could cause results to differ materially from those expressed in the forward-looking statements contained in this release include, but are not limited to: issues relating to the operation of complex operations such as upgrading of oil sands; labour and cost pressures in the oil sands industry and in the Fort McMurray area in particular; the regulatory changes that impact oil and gas operations; the nature of the regulations imposed by the federal government on income trusts; general economic, business and market conditions; commodity prices; and such other risks and uncertainties described from time to time in the reports and filings made with securities regulatory authorities by the Trust. You are cautioned that the foregoing list of important factors is not exhaustive.  Furthermore, the forward-looking statements contained in this release are made as of the date of this release, and the Trust does not undertake any obligation to update publicly or to revise any of the included forward-looking statements, whether as a result of new information, future events or otherwise.  The forward-looking statements contained in this release are expressly qualified by this cautionary statement. The information was approved by management on December 5, 2007 and circumstances after this date may change the outcomes or results achieved.

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Canadian Oil Sands Limited
Trevor Roberts
Chief Operations Officer
(403) 218-6214

Units Listed – Symbol: COS.UN
Toronto Stock Exchange
 For further information:

Rob Dawson
Treasurer
(403) 218-6225
investor_relations@cos-trust.com

Web site: www.cos-trust.com