Clean Diesel announces the appointment of new Chief Financial Officer.

STAMFORD, Conn. -- Clean Diesel Technologies, Inc. ("Clean Diesel" or the "Company") (EBB: CDTI & AIM: CDT/CDTS), a developer of technological solutions to reduce harmful engine emissions, today announces the appointment of Ann Ruple as the Chief Financial Officer & Vice President, Administration of the Company, effective Wednesday, December 13, 2006. The appointment comes at a turning point for the Company, with high diesel fuel prices, requirements to control engine emissions and concerns about global warming being key issues throughout the world. Clean Diesel benefits from its strong IP position in the emission and energy efficiency reduction market.

Prior to joining Clean Diesel, Ann Ruple, CPA, was most recently Director of Financial Planning and Analysis of NCT Group, Inc., a US publicly-traded, high-tech company with a strong technology base, a position she held for more than eight years. At NCT Group, Ann was responsible for SEC reporting including the filing of numerous registration statements required by issuance of convertible securities. In addition, she developed and implemented various models for business units within the firm to evaluate and improve accountability, financial controls and forecasts with a focus on liquidity, expense control and return on investment. Prior to NCT Group, Ann held various senior management positions in both private and publicly-traded US companies and brings extensive technology and small cap experience to Clean Diesel. Ann's career foundation includes four years with PriceWaterhouse Coopers.

Ann will report directly to Dr. Bernhard Steiner, President and CEO of Clean Diesel. Dr. Steiner said: "Ann's considerable skills in financial planning and analysis, together with her understanding of technology, will be important assets to Clean Diesel. Ann is a very strong addition to our senior management team; her technical and business acumen along with her deep understanding of the regulatory framework in the US will ensure that we continue to grow in a systematic and measured way, while at the same time applying meticulous attention to cash management. We are delighted to welcome her to this critical leadership role."

Commenting on her appointment, Ann Ruple said: "I am pleased to join the Company at this exciting time. With increased legislation and norms in the US, UK and Europe, companies are under more and more pressure to reduce their emissions which will further increase the demand for Clean Diesel's technologies and licenses. My background and experience in publicly-listed technology companies with strong IP positions is a great fit with Clean Diesel, and I look forward to making contributions to the Company's healthy growth."

There are no further disclosures to be made regarding this appointment under Schedule 2 paragraph (g) of the AIM rules.

Notes to editor

Clean Diesel Technologies, Inc. and its UK representative office, Clean Diesel International LLC, is a developer of technological solutions to reduce harmful engine emissions. Clean Diesel Technologies has patented products that reduce emissions from combustion engines while simultaneously improving fuel economy and power. Products include Platinum Plus([R]) fuel-borne catalysts (FBC), the Platinum Plus Purifier System and the ARIS([R]) 2000 urea-injection systems for selective catalytic reduction of NOx. Platinum Plus and ARIS are registered trademarks of Clean Diesel Technologies, Inc. For more information, visit CDT at www.cdti.com or contact the Company directly.

Certain statements in this news release constitute "forward-looking statements" within the meaning of the Private Securities Litigation Reform Act of 1995. Such forward-looking statements involve known or unknown risks, including those detailed in the Company's filings with the Securities and Exchange Commission, uncertainties and other factors which may cause the actual results, performance or achievements of the Company, or industry results, to be materially different from any future results, performance or achievements expressed or implied by such forward-looking statements. Readers are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date hereof.