Answer: The concept of the five-fold ministry comes from Ephesians 4:11, "It was he who gave some to be (1) apostles, some to be (2) prophets, some to be (3) evangelists, and some to be (4) pastors and (5) teachers." Primarily as a result of this verse, some believe God has restored, or is restoring, the offices of apostles and prophet in the church today. Ephesians 4:12-13 tells us that the purpose of the five-fold ministry is, "to prepare God's people for works of service, so that the body of Christ may be built up until we all reach unity in the faith and in the knowledge of the Son of God and become mature, attaining to the whole measure of the fullness of Christ." So, since the body of Christ definitely is not built up to unity in the faith and has not attained to the whole measure of the fullness of Christ - the offices of apostle and prophet must still be in effect.
However, Ephesians 2:20 informs us that the church is, "built on the foundation of the apostles and prophets, with Christ Jesus Himself as the chief cornerstone." If the apostles and prophets were the foundation of the church, are we still building the foundation? Hebrews 6:1-3 encourages us to move on from the foundation. Although Jesus Christ is most definitely active in the church today, His role as the cornerstone of the church was completed with His death, burial, resurrection, and ascension. If the work of the cornerstone is, in that sense, complete - so must the work of the apostles and prophets, who were the foundation.