In 1980, Brazil was the largest Roman Catholic country in the world, with 90 percent of its more than 120 million people numbered among the faithful. The Church hierarchy became aware, however, that the religion practiced by the majority of its members was not that promoted by the institution, a point dramatized by the rapid growth of other religious movements in Brazil—particularly Protestant sects and spirit-possession cults. In response, the Church created and assumed new roles. The Church in Brazil is a case study of the changes within the Church and their impact on Brazilian society.

In an original and illuminating discussion, Thomas Bruneau combines institutional analysis and survey data to explore the relationship between structural changes in the Church and evolving patterns of practice and belief. His discussion displays the richness and variety of devotion in Brazil—characteristics recognized by many observers—and examines the Church's potential for influencing the people's religious life.

Moving from the historical and national to the regional, Bruneau analyzes and compares changes among eight dioceses. He concludes that the Church is actively promoting a progressive social role for itself and, by backing its statements with actions, is perceived as being socially effective by both supporters and opponents.

The first study in which the national and diocesan levels of the Church are analyzed together, it is also the first to inspect systematically the Basic Christian Communities, thought by some to be the most significant grass-roots movement in the Catholic world of that time.