Forest certification is a practice that has been consolidated worldwide in recent years as a result of certification often being associated with sustainability. However, there is not much research available on the perception of stakeholders and experts of that association. This study evaluates how key stakeholders relate certification to sustainability, and its implications for forest management. A survey was implemented in the eucalyptus plantations of Galicia, northwestern Spain, to assess how forest managers; advisors; environmental organizations; researchers; and members from the FSC (Forest Stewardship Council), PEFC (the Program for Endorsement of Forest Certification), and forest companies and associations, perceive this relationship. The opinions indicate that it should not be assumed that certified plantations are necessarily perceived as the most sustainable ones, that there is always a direct relationship between certification, nor that forest owners and managers certify their woodlands in order to guarantee sustainability. The results also showed that perceptions of certification and sustainability were not influenced by the opinions of different groups of stakeholders.