EXHIBIT A

JOINT FILING AGREEMENT

This Joint Filing Agreement (this “Agreement”) hereby confirms the agreement by and among all of the undersigned that the Schedule 13G to which this Agreement is attached as Exhibit A with respect to the beneficial ownership of the undersigned of shares Common Stock of Westport Innovations Inc. is being filed on behalf of each of the undersigned. This Agreement may be executed in two or more counterparts, each of which shall be deemed an original, but all of which together shall constitute one and the same instrument.

Date: February 18, 2010	* Kevin Douglas
	Kevin Douglas
Date: February 18, 2010	* Michelle Douglas
	Michelle Douglas
Date: February 18 2010	* James E. Douglas III
	James E. Douglas III
	K&M Douglas Trust
Date: February 18 2010	* Kevin Douglas
	By:	Kevin Douglas
	Title:	Trustee
Date: February 18, 2010	* Michelle Douglas
	By:	Michelle Douglas
	Title:	Trustee
	Douglas Family Trust
Dated: February 18, 2010	* James E. Douglas, Jr.
	By:	James E. Douglas, Jr.
	Title:	Trustee
Date: February 18, 2010	* Jean A. Douglas
	By:	Jean A. Douglas
	Title:	Trustee
	James Douglas And Jean Douglas Irrevocable Descendants’ Trust
Date: February 18, 2010	* Kevin Douglas
	By:	Kevin Douglas
	Title:	Trustee
Date: February 18, 2010	* Michelle Douglas
	By:	Michelle Douglas
	Title:	Trustee

*By:	/s/ Eileen Davis Wheatman
	Eileen Davis-Wheatman
	Attorney-in-fact