This book details the process of the transformation of monastic Daoism of the Quanzhen (Complete Perfection) order after the Cultural Revolution. When religious activities were again permitted in 1979, Daoism had only twenty-one monasteries. By 2014, there were 30,000 Daoist temples and 100,000 clerics. This expansion occurred in an overall supportive political context, involving the government, the Chinese Daoist Association, and many local priests who reoriented their practice from personal cultivation to temple building and the spread of longevity techniques while also opening their teachings to foreigners. The climate changed again in 2018, with the policy of "sinification" which now requires all religions to represent Xi Jinping thought and severely limits their activities. The book uses the Thunder Drum (Leigutai) lineage in Ziyang county, Shaanxi as a model to analyse the modifications at the organizational and doctrinal level that continuously require Daoists to adapt to ever-new political and social contexts. It is a pioneering work, essential for our understanding of religion and culture in China today.