High Nature Value (HNV) farming systems are inherently valuable for biodiversity. They use semi-natural pastures, meadows and orchards, as well as species-rich arable land, and often retain a wealth of landscape features. HNV farming is present in all European countries, with a diversity of types and extent. Apart from being the cornerstone of European farmland biodiversity, these types of farming provide a multitude of other services for society, including sustainable rural economies, and the rich social fabric and character of Europe’s landscapes. The environmental, socio-cultural and territorial significance of HNV farming is increasingly recognised, but greater awareness is needed amongst policy makers and the wider public. This chapter on Portugal is part of a book presenting an overview of HNV farming across 35 European countries, describing the main characteristics and presenting examples of farming systems, farms and farmers. Beside the country chapters there are thematic chapters looking at a range of issues of farming, nature, economy and policy. In Portugal exists an immensely rich heritage of traditional farming systems, almost all of which are still of High Nature Value. Some of these use large-scale semi-natural areas – the baldios and lameiros of the north and the montado in the south. Others are characterised by low-intensity mosaics – small-scale permanent cropping farms in the south and especially the typical smallholdings of the northern uplands. Both the area of farmland and the number of farmers have declined steeply over recent years; all HNV farmland associated with small farms are in practice severely threatened. On the southern latifundia, the picture is more complex – cork prices maintain a relatively good income, but the quality of management of many montados is in decline, with both localised intensification and abandonment. New intensive systems are being put in place, included irrigated low nature value olive monocultures. A territorial vision for Portugal’s agricultural landscapes is only in its infancy; this is a severe impediment to the development of holistic and targeted support for HNV farming systems. Economic marginalisation has allowed the survival of Portuguese HNV farming systems into the early 21st century; a socio-economically and ecologically sustainable future for those systems or their modern successors requires an end to their political marginalisation.