The success of organic farming systems is in large part due to biological diversity and nutrient recycling.   In Canada, most organic farms have converted from low diversity, fertilizer intensive management systems.  In Asia, many organic systems did not go through the “green revolution” phase; farmers have made less dramatic adjustments to their systems over time.  The first objective of the paper is to contrast how different starting points affect the thinking, transition strategy and ultimate design of organic systems.  We will discuss how previous experiences affect adaptive management ability among farmers.  The second objective considers how organic systems have needed to change in response to declining production, weather abnormalities, pests and changing markets.  Here, we will provide examples from long-term studies in Canada and Asia.  Organic farming systems are dynamic and must adapt to environmental and market forces.  Farmers must use adaptive management strategies to adjust to changing forces.  Farm advisors must understand adaptive management as a tool for continuous system improvement.  Finally, scientists must focus on systems that facilitate adaptive changes in farm management with a view to increasing system resilience.