Many methods of foreign/second language teaching were developed in the past. However, there is no one method of language teaching to suit all circumstances. Accordingly, a method can be more effective if the best ideas from other methods are assimilated. It is because the method should suit the teachers, the students, and other classroom environments. In fact, the integrated method is always used, with such ideas stated above and realities. The rationale of integration is discussed based on the language teaching theories and reality in Korean schools. All theories support the idea of integration. Students, teachers, and other factors in reality also support the idea of integration.