The solidarity，concentration and unity are the life of the Party and the key to the Party’s success in becoming a centennial Party and creating great achievements. Over the past century，the Communist Party of China has attached great importance to promoting the construction of the organizational system of centralized and unified leadership. During the new democratic revolution period，unified leadership system and request for instructions and reporting system have laid the preliminary foundation for the Party’s centralized and unified leadership；During the period of socialist revolution and construction，the CPC Central Committee effectively improved the loose state between the central and local governments by strengthening its own authority and centralized and unified leadership；During the period of reform and opening-up and socialist modernization，the gradual improvement of democratic centralism provided an important guarantee for the restoration of the Party’s centralized and unified leadership；Since the new era，upholding the authority of the CPC Central Committee and centralized and unified leadership has been comprehensively optimized in terms of theory，system and practice，reaching a new historical height. It’s precisely because of the Party’s centralized and unified leadership that the Chinese people have created a series of great achievements and solved many development problems. Therefore，the Party’s centralized and unified leadership must be adhered to all the time.