In pharma industry quality is important.Drug quality depends more on production, best development, storage, and distribution strategies. PAT focuses on the principles of building quality into the product and process as well as continuous process improvement. PAT is based on belief that quality cannot be tested into the products it should be built in or should be by design. PAT promises to provide benefits to both consumers and manufactures of pharmaceutical products. Such technology will improve manufacturing efficiency while enhancing process understanding. PAT is the process of understanding and control it is not easy to implement. For successful implementation of PAT co-ordination, flexibility, communication between the staff is very important. PAT processes are deemed successful on the basis of significant process understanding. PAT is applied in every step of manufacturing of pharmaceutical product. PAT generally uses pioneering technologies like FTIR, NIR, ATIR, NMR.