Ian Alexander is an independent consultant, trainer and author specializing in Requirements Engineering, often using DOORS / DXL as the platform.
He has worked with organizations in transportation, telecommunications, aerospace, government and public service in the UK and around the world, on both implementation projects and process support.
He is the lead author of Writing Better Requirements (Addison-Wesley, 2002), Scenarios, Stories, Use Cases (Wiley, 2004), and Discovering Requirements (Wiley, 2009) (http://www.scenarioplus.org.uk). There are many free resources for use in discovering and organizing requirements on his website.
He is currently (2010) chairman of the BCS Requirements Engineering Specialist Group (http://www.resg.org.uk). He is a Chartered Engineer.