IT offshoring is becoming increasingly important for the competitiveness of companies that outsource some parts of their business processes to distant countries. The basis of a successful IT offshoring project is what is known as knowledge transfer: the knowledge available within the company must be communicated to employees in the overseas-based part of the company in a sustainable manner so that they can perform their tasks as part of a global value chain. Effective and efficient knowledge transfer depends on a number of critical success factors. This thesis therefore examines which factors have a significant influence on the effectiveness and efficiency of knowledge transfer in IT offshoring. This results in an evaluation model with which two countries, Russia and India, were examined and compared as important offshoring destination countries.