The name is generally used to describe that section of the valley of the River Colne that lies between its source and the large town of Huddersfield, which lies at the point where the River Holme joins the River Colne. Less often, the name is used to describe the whole valley of the Colne, including the section through Huddersfield and on to the confluence of the Colne with the River Calder at Cooper Bridge. Using the more common definition, the Colne Valley includes the towns and villages of Marsden, Slaithwaite, Linthwaite and Golcar.
By the end of the Second World War, the importance of the Colne Valley as a centre of textile production had begun to decrease. The area is now primarily residential, its excellent transport links making it ideal for commuters. Tourism is being promoted: the Huddersfield Narrow Canal was reopened in 2001 and boat trips into Standedge Canal Tunnel are available; the National Trust advertises walks on Marsden Moor Estate; and television programmes such as Last of the Summer Wine and Where the Heart Is have been filmed there.
The Colne Valley parliamentary constituency still preserves the usage of the Colne Valley name for an administrative entity, although the constituency also includes the Holme Valley, Meltham and some outskirts of Huddersfield. Notable former MPs for the constituency include Victor Grayson and Richard Wainwright.