§1. To confer the presbyteral or diaconal orders licitly, it is required that the candidate, having completed the period of probation according to the norm of law, is endowed in the judgment of his own bishop or of the competent major superior with the necessary qualities, is prevented by no irregularity and no impediment, and has fulfilled the prerequisites according to the norm of cann. 1033-1039. Moreover, the documents mentioned in can. 1050 are to be obtained and the investigation mentioned in can. 1051 is to be completed.
§2. Furthermore, it is required that he is considered in the judgment of the same legitimate superior as useful for the ministry of the Church.
§3. The bishop ordaining his own subject who is destined to the service of another diocese must be sure that the one to be ordained is going to be attached to this other diocese.
Source: Code of Canon Law (Vatican.va)