Canonical Visitation

A canonical visitation or apostolic visitation is "an exceptional initiative of the Holy See which involves sending a Visitor or Visitors to evaluate an ecclesiastical institute such as a seminary, diocese, or religious institute. Apostolic Visitations are intended to assist the institute in question to improve the way in which it carries out its function in the life of the Church."

The practice was re-established in the Catholic Church by the Council of Trent (1545 to 1563) in these words:

Patriarchs, primates, metropolitans and bishops shall not fail to visit their respective dioceses either personally, or if they be lawfully hindered, by their Vicar-general or visitor; if they shall not be able on account of its extent, to make the visitation of the whole [diocese] annually, they shall visit at least the greater part thereof, so that the whole shall be completed [with]in two years, either by themselves or by their visitors.

Of the purpose of visitation the Council says:

But the principal object of all the visitations shall be to lead to sound and orthodox doctrine, by banishing heresies; to maintain good morals, and to correct such as are evil; to animate the people, by exhortations and admonitions, to religion, peacefulness, and innocence; and to establish such other things as to the prudence of the visitors shall seem for the profit of the faithful, according as time, place and opportunity shall allow.

The right of visitation belongs to all prelates who have ordinary jurisdiction over persons in the external forum. The pope through his delegates may institute a visitation throughout the world, patriarchs, primates, metropolitans, bishops, a vicar apostolic and a vicar capitular or administrator of a vacant diocese, all in their respective territories, religious superiors within their own jurisdiction. A prelate nullius enjoys this right in conjunction with the neighbouring bishop, whose precepts in case of disagreement will prevail. Visitation does not, however, fall within the province of a vicar-general unless he be specially commissioned by the bishop. A metropolitan is not permitted to visit the dioceses of his suffragan bishops save for reasons approved in a provincial synod, and then only after the visitation of his own diocese has been completed.

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Wikipedia