The environmental movement in Pittsburgh, like the national movement, has ebbed and flowed over time (Ogrodnik and Staggenborg 2016). Some local organizations, such as the Group against Smog and Pollution and the Allegheny Group of the Sierra Club, have survived since the 1970s, albeit with fluctuating levels of activity. Many other groups have come and gone, though they often have impacts beyond their lifetimes as active organizations, such as the creation of networks and changes in public discourse. The movement has experienced ups and downs as new issues motivate supporters and later recede in urgency. Individuals often become involved in social movements during periods of threat, when issues and organizing efforts are visible. As we saw in Chapter 5, some of the early opponents of fracking in Pittsburgh were newcomers to the local environmental movement who, as residents of city neighborhoods threatened by fracking, became aware of the issue. Movement organizers had to devise ongoing tactics and create organizational structures that would involve supporters and maintain the movement. This was difficult to keep up over time, and Marcellus Protest, Shadbush, and Protect Our Parks all eventually stopped meeting. Nevertheless, the movement continued.