With the objective of improving overall performance of the steam assisted gravity drainage (SAGD) enhanced oil recovery (EOR) process, the industry has invested time and resources in developing representative models to better understand the different parts of this complex thermal system. In SAGD projects, steam injection and production wells are typically analyzed by steady-state flow models. On the other hand, transient models are used to model the reservoir and the in situ thermal process. This study presents the benefits of an integration of engineering models (steam injection, reservoir and production process) in a single, seamless SAGD integrated asset model (IAM). The purpose of the integrated model is to analyze the impact of the surface facilities on the reservoir with the aim to improve the understanding the effect of the injection in the SAGD process and optimize the operational and capital expenditures. This study also uses a probabilistic approach to the main sources of uncertainty and it also controls key aspects of the SAGD field development plan. Uncertainties were included in different reservoir realizations, allowing the evaluation of an electric submersible pump (ESP) artificial lift system design and boiler steam injection capacity. The integration between the surface and subsurface models improved the representation of the overall SAGD process, increasing resolution in the recovery calculations and helping the decision-making through collaboration between reservoir, production and facility engineers. The combination allows the identification of the most cost effective configuration for this well pair, considering the most common technologies used in the SAGD process. While the integrated asset modeling approach is not, in itself, new, we believe this is the first time a fully coupled SAGD process has been considered, and to improve the production based on the injection temperature, steam quality, and ESP design parameters.