Throughout Latin America, substantial areas of forestland have been devolved to rural indigenous and traditionally forest-dependent rural populations (Barry and Taylor, 2008; Larson et al, 2010; see also Chapter 2 in this volume). Frequently forest-based social movements have played important roles in pressuring national governments to demarcate and recognize property rights (Brechin et al, 2003; Merry et al, 2006; Cronkleton et al, 2008; Sunderlin et al, 2008). These groups have relied on collective action to assert claims over forest resources, defend productive interests and traditional livelihoods, and give voice to rural views of development policy. Where they have emerged successfully, the rights gained by forest-based social movements have dramatically improved the property rights security of participants and expanded control over immense territories, usually with collective rights over communal lands. These movements often seek recognition of customary or traditional rights staked out historically and try to ensure that local people maintain control over forest benefits. However, the property and resource rights acquired by such movements also entailed significant limitations that can undercut overall benefits (Larson et al, 2008; Sunderlin et al, 2008). In addition, the incremental advance in rights recognition can defuse the original catalyst for collective action. As a result, leaders of grassroots movements need to work to maintain relevance and defend newly gained rights (Cronkleton et al, 2008).