Forest certification is the process by which an independent third party certifies that a forest management process or forest product conforms to agreed standards and requirements.1 Two types of standards may be promoted in certification schemes: systems-based standards and performance-based standards (see Box 6.1). The certification wars referred to here are the valuebased disagreements and conflicts between the proponents of the different non-state, market-based forest certification schemes that have emerged since the mid 1990s, particularly between the Forest Stewardship Council (FSC) and various business-promoted schemes that have challenged the FSC. The struggle between the FSC and these competitor schemes has assumed the form of a struggle for global hegemony and, as with all hegemonic struggles, those involved, namely the supporters of the different schemes, have sought to gain legitimacy and authority through action across a broad range of sites. This chapter provides an analytical overview of the certification wars in, more or less, chronological order. We argue that the certification wars symbolize a deeper conflict about who makes the rules of global environmental governance, and in whose interests.