Advanced well concepts including horizontal and multilateral wells have become a dominant feature of new field development and redevelopment opportunities. They can, when used appropriately, dramatically improve the economic profitability of field development operations. However, the success of deployment largely depends on the effectiveness of assessment of the longer term production dynamics essential to ensuring “life of well” design criteria and effective reservoir management.The course will discuss the subjects of multilateral well applications, pros and cons, the classification of junction and completion, well performance, and problem diagnosis. The application and benefits of horizontal and multilateral wells are analyzed. Methods to predict well performance and recovery from horizontal and multilateral wells are presented. The integration of inflow and wellbore flow performance for individual horizontal and multilateral wells is discussed. Well completion options for horizontal and multilateral wells are summarized. The objective is to be able to identify the candidates for the technology, and to be able to design a well that will optimize production.