Postcursillo is to renew, accelerate, and continue the conversion of each individual who has experienced the 3-Day Cursillo and encountered the love of our Lord Jesus Christ!

Within the Postcursillo there are two basic means for growing and persevering in the Christian life: the Group Reunion for individuals, and the Ultreya for the community. Although both of these are community structures, Group Reunion is directed primarily toward the good of the individual, the Ultreya toward the good of the community as such. In terms of method, both are essential. An isolated Christian is a paralyzed Christian. The same is also true of any group that is not connected with other groups.
(The Fundamental Ideas of the Cursillo Movement)