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In the recent past several international conferences have been devoted to the duplex stainless steel ( DSS) family.Those conferences have pointed out the success story of DSS particularly when considering project business in several areas of applications including oil & gas,petrochemical,chemical,pulp & paper industries as well as water systems and desalination.Most of the products concerned hot rolled,highly alloyed grades or seamless pipes.The benefits of those technical products have been confirmed.They present high mechanical and corrosion resistance properties.As a result when properly specified and transformed,significant cost reductions could be achieved through weight and maintenance cost savings.The recent major trends concern the development of less alloyed grades having almost Mo-free and extra low-Ni content,the development of thinner gauge products ( down to less than 1mm) and even higher mechanical properties.Several compositions have been proposed and new applications foreseen.The main challenge is to propose alternative dual- phase alloys with improved mechanical properties but equivalent corrosion resistance compared to the austenitic 304/316 grades.The paper will present some technical challenges related to the development of those grades as well as there respective behaviour when considering mechanical,corrosion resistance properties and weldability.The grades are also beside the classical capital goods markets,targeting new duplex applications in Building & Construction like water systems,hot water tanks,and structural applications.The paper will continue the review of the new developments of the duplex family by presenting the newly developed grades having for most of them a maximum of 1.5% Mo and a partial replacement of Ni by combined nitrogen and Mn additions.Some more alloyed grades have been also recently proposed.Have those grades a bright future with the development of new markets or bring even more confusion in our stainless world? Are they "project" oriented grades or a new opportunity for future volume markets? Finally some guidelines concerning the duplex grades specifications and quality control aspects will be discussed.