Use of extended reach drilling (ERD) practices has become a common means to economically access reserves from existing infrastructure, provide the way to reserves that were previously out of reach, and reduce the environmental footprint of drilling and production facilities. Unfortunately, in industry there are still a lot of ERD wells that have been lost or made uneconomic by a lack of effective planning, especially planning of running casing into the lower intervals. Casing running normally takes only a small percentage of the well development life cycle. However, the consequences of failing to get the casing to section total depth are normally very significant of quality time in well planning. Thus, development of clear procedures and active management of this operation will usually give a high success rate. Within this master thesis an integrated approach to mitigate problems during casing the long 12-1/4 inch section with 9-5/8 inch liner in a new ERD well in Russian offshore field is suggested. Firstly, the analysis of common torque and drag, borehole cleaning, hydraulics and other challenges specific to casing running job are analyzed. Furthermore, there is an overview of the best practices and possible measures to overcome or prevent those issues. In the case study the experience of 4 ERD wells is presented and the whole process of liner running job in the planned well, including hole cleaning and setting of liner-top packer, is discussed.