A number of yield improving viticultural practices were assessed in terms of their effect on wine quality. These were improved soil management, lighter pruning/higher trellis, irrigation and a control. In the first year a yield increase of 1.6 t /ha for the irrigation treatment had no significant effect on wine quality. A procedure is presented to assess judges for reliability, discrimination, variability and stability as part of analysis of the sensory results. Four judges were able to consistently identify lot differences