Organic pig production systems seek to produce pig meat in a more ethical and natural manner. This involves adherence to standards relating to accommodation, feeding, health management, husbandry and behavioural freedom which differ from conventional pig production practice. To be sustainable, organic systems must command a market premium by demonstrating differentiation in terms of enhanced animal welfare and reduced environmental impact, whilst ensuring safety and healthiness of products. Whilst some of these claims can be justified, others are open to challenge in current systems. A great diversity in organic production systems and the outcomes which they achieve is apparent, but the growing organic market is leading to increasing research into organic pig production and continuous system improvement.