The European dairy industry faces an increasingly uncertain world. There is uncertainty about subsidy payment levels and compliance conditions, global competition, price variability, consumer demand, carbon footprints, water quality, biodiversity, landscapes, animal welfare, food safety, etc. The future is uncertain because it cannot be reliably predicted; therefore the industry must adopt production systems that will be financially robust over a wide range of possible circumstances. Adding to the uncertainty is a lack of consensus regarding the specific characteristics of these sustainable production systems. In this interdisciplinary research project we developed a profit maximizing whole-farm model and employ it to identify robust milk production systems for Northern Ireland under varying market, policy and farm family conditions. The milk production systems incorporated into the model involve variations in date of calving, quantity of concentrate fed, and nature of forage utilized. The model also incorporates a disaggregated specification of time use within farm households and links intra-household resource allocation to the process of agricultural technology adoption. This work illustrates how profit maximizing whole-farm models can play a decision support role in helping farmers, agricultural researchers, agribusiness advisers and agricultural policy makers to identify economically sustainable agricultural production systems.