In the last decades, the negative environment impacts of entreprise activities have gained wide recognition. Environmental issues affect numerous logistical decisions troughout the value chain. As concerns rises, companies must take more account of the external logistics cost related with the environment problems (such as climate change, pollution and scarcity of natural resources) and social problems (poverty, violence, unemployment...) Several studies suggest that green logistics strategies such as reducing consumption, recycling and reusing materials can bring large benefits. Companies should be able to create measures and strategies in order to achieve sustainable balance between economic, environmental and social objectives. This research intends to identify logistics-related environmental impacts in activities such as purchasing (raw materials acquisition), Transport, Warehousing/Distribution; to interpret concepts such as Green Logistics and Inverse Logistics; to present an international Case Study (Procter & Gamble) and a Portuguese Case Study (Unicer), showing the best practices employed by leading firms; finnaly, an overview of managers opinion about environmental and social problems, sustainable reports and environmental responsible logistics activities.