Supreme Pontiff: Beatification
With the beatification rite, conducted on the authority of the Supreme Pontiff, the Venerable Servant of God is declared Blessed.
Blesseds may receive public veneration at the local or regional level, usually restricted to those dioceses or religious institutes closely associated with the person's life. "Public veneration" in this use of the term doesn't mean that it is done in public; rather, that it is an act done by the clergy, or delegated laity, in the name of the Church (Mass, Divine Office, images in churches etc.), even if done in private. On the other hand, "private veneration" means veneration by individuals or groups acting in their own name, even if done "in public." While the Church restricts the public veneration of Blesseds, Catholics are free to privately venerate them.
The reason for this distinction and its disciplinary norm is that beatification is not considered an infallible papal act, and so it is not yet appropriate that the entire Church give liturgical veneration to the Blessed. Perhaps to reinforce this distinction, Pope Benedict XVI has restored the practice, in use prior to Pope Paul VI, of having the Prefect of the Congregation conduct the beatification, rather than the Pope doing it himself. He has made exceptions, one of which is his predecessor, Pope John Paul II.
In the case of Blessed John Paul II, the Holy See in a Decree Concerning the Liturgical Cult of Blessed John Paul II has determined that public veneration is lawful in the Diocese of Rome and the nation of Poland. Other nations, dioceses and institutes may petition the Congregation for Divine Worship and the Discipline of the Sacraments for the Indult to render cultus (veneration) to the Blessed. Without an Indult, however, public veneration is illicit, and even harms the possibility for Canonization of the Blessed.
Diocese: Second Miracle Proposed in Support of the Cause
After beatification, the Church looks for a second miracle before proceeding to canonization. The process is the same as it was for the miracle, which made beatification possible. The alleged miracle is studied by scientific and theological commissions in the diocese in which it is alleged to have occurred.
Congregation: Second Miracle Proposed in Support of the Cause
After the diocesan process is concluded the proposed miracle is studied by a scientific and then a theological commission of the Congregation for the Causes of the Saints. The vote of this commission is forwarded to the episcopal members of the Congregation whose affirmative vote is communicated to the Holy Father.
Supreme Pontiff: Decree of a Miracle
The consent of the Holy Father to the decision of the Congregation results in a Decree of a Miracle. Canonization is now possible.