Sewage Treatment is undertaken to ensure sanitation, avoid spread of water borne diseases; prevent water pollution and also to protect environment and aquatic life. Developing countries such as India, which face burgeoning population and consequent effects of untreated sewage; sewage treatment has become an important policy decision for Urban Local Bodies (ULB's). This paper gives a brief description of Cyclic Activated Technology; a modern technology for sewage treatment along with its implementation vis-à-vis a case study of 50 MLD STP at Chandigarh.