A company's competitive advantage is most likely to be sustained over time through the advanced factors of production such as process knowledge, organizational architecture, and intellectual property. In fact, the above-mentioned resources are likely to be rare and more difficult for rivals to imitate. In regards to process knowledge and organizational architecture, there are no two organizations with the same process or architecture these two resources are believed to be rare. The same applies to process knowledge and intellectual property. In fact, the latter is so unique that it is protected by patents, copyrights etc. In addition, all there advances advanced resources have high barriers to imitation. In other words, there are extremely difficult for another company to replicate. When advanced factors of production are also valuable and well organized, they can positively contribute to the efficiency, innovation, customer responsiveness and quality - these 4 are believed to be building blocks of competitive advantage.