Only procedures and experiments described in the approved protocol may be conducted. Significant changes in animal-use activities require that the investigator receives approval of the proposed changes from the IACUC prior to implementation. These changes must be described in a "Modification Memorandum" to the committee.

A modification to an approved application undergoes the same review process as do new or renewal applications. Investigators should allow 2-3 weeks for review of modifications by the IACUC.

Such minor alterations to an approved application as changes in funding, personnel, or facilities must also be submitted to the committee in a "Modification Memorandum." Minor changes of an administrative nature can usually be processed within 7-10 days.