Lens belongs to the intercommunality of Lens-Liévin, which consists of 36 communes, with a total population of 250,000. Lens, along with Douai, forms the metropolitan area of Douai-Lens, whose population at the 1999 census was 552,682.
The city is an industrial and has a long history of coal mining. Surrounding the town are many large slag heaps, evidence of over a hundred years of mining, which came to an end in the 1960s.