How did the caltholic church respond to the Protestant reformation

Counter-Reformation, also called Catholic Reformation or Catholic Revival, in the history of Christianity, the Roman Catholic efforts directed in the 16th and early 17th centuries both against the Protestant Reformation and toward internal renewal. The Counter-Reformation took place during roughly the same period as the Protestant Reformation, actually (according to some sources) beginning shortly before Martin Luther's act of nailing the Ninety-five Theses to the door of Castle Church in 1517.