This technical guide provides background information and data on used oils, information on ecolabelling for lubricants and alternatives such as bio-lubricants, associated environmental problems caused by used oils as well as information on the main used oil treatment technologies. It also describes in plain and simple language the possible steps towards the environmentally sound management of used oils that can generally be applied to any given country that goes from stakeholder engagement to final rerefining/ recycling and shows several case studies on used oil pollution prevention.