Financial indicators of sustainability, developed using a combination of value based management and environmental accounting techniques, are applied to both time scries data and case study farms to identify any underlying trends of concern that might indicate that the long term survival, or sustainability, of the farms is at risk. Using time scries data from both sheep and beef cattle farms and dairy farms this study explored the relationships that exist over time between a number of performance measures with a view to determining some of the key drivers of both viability and sustainability, for farm businesses. Because of the volatility of financial results the average change in values over a period of greater than three years was used as the basis from which to identify trends. The three drivers suggested as having the most influence on farmer decision making long-term are operating profit, capital gain and the cost of capital (debt and equity).