As Secretary of State for Transport, Ridley performed a key function in building up coal stocks in advance of the 1984–85 miners' strike, which helped the government to defeat the National Union of Mineworkers (NUM). As Secretary of State for the Environment, Ridley opposed a low-cost housing development near his own property, earning him the title of "NIMBY" ("Not in My Back Yard"). He was also responsible for introducing the "poll tax" (formally known as the Community Charge), which was one of the main factors leading to Thatcher's resignation in 1990. He was created a life peer in 1992.