Producing products of recognised and differentiated quality entails a competitive advantage for agro-food agents since consumers are increasingly demanding high-quality food and control in the production process as a whole in a transparent and verifiable manner. Certification of products and processes through the implementation of Certified Quality Systems (CQS) are voluntary and guarantees standards of quality beyond conventional and mandatory levels. CQS include European, national and regional regulations (such as Protected Designation of Origin – PDO, organic and integrated agriculture), ISO norms (such as 9000, 14001, 19011, and 22000), private protocols (GLOBALGAP, International Food Standard - IFS, Nature’s Choice, etc.), and specific regulations for particular products, among others. This work focuses on the olive growing sector of Andalusia, an agricultural sector of fundamental importance in economic, social and environmental terms in this region of Spain. In fact, Andalusia is the world leading olive region. Although the ‘quality strategy’ is widely recognised as fundamental in the agro-food system, in the Andalusian olive sector it is only based on the implementation of some few CQS while other are scarcely known and adopted. Moreover, the adoption of a particular CQS does not necessarily entail the implementation of the agricultural practices optimal from an environmental, economic and/or agronomic point of view. Given the current situation of globalisation of the markets and advent of new olive producing regions in the world, and of increasing quality demand from consumers, the competitiveness of the Andalusian olive sector could be at risk in the medium to long term. In this context, the aim of this paper is threefold: (1) describing the situation of the knowledge and adoption of diverse CQS in the olive farming sector of Andalusia; (2) analysing the factors related to the adoption of PDO; (3) identifying agricultural practices associated to the adoption of PDO and assessing their goodness from an environmental, economic and/or agronomic point of view. The research is based on a survey carried out in 2010 to 200 farmers of the main olive growing zones of Andalusia. Analysed CQS include the most relevant and potentially implementable systems in olive production, but we will specially focus on PDO (Protected Designation of Origin) because for this CQS the adoption rate is the highest to obtain statistically significant results and conclusions and because it has been less examined in the literature. Analysed variables refer to both (a) characteristics, attitudes and opinions of farmers, such as agricultural training, sources of information about CQS, objectives Ascensión Hinojosa-Rodríguez et al. 329 when producing, objectives when innovating, difficulties to innovate, priorities in R&D, among others; and (b) characteristics of farms, such as location, farm area distribution, yield, type of labour force, destination of the production, slope of the land, among others. Analysed farming practices refer to soil management, irrigation, fertilization, phytosanitary treatments, and harvest.