Our actions have large impacts on the environment. These actions include individual actions taken by one person and collective actions taken by groups of people. While we can make a difference through our individual actions, collective actions pose some distinct challenges worthy of dedicated attention. In particular, collective action problems occur when individual interest conflicts with group interest. One type of collective action problem is the tragedy of the commons, which involves the sustainability of natural resources. Collective action problems such as the tragedy of the commons can be avoided. The three main types of solutions are government regulation, private ownership, and community self-organization. Depending on interactions with larger-scale factors, such as global market forces and climate change, any of these basic solutions may not be sufficient on its own.