Marriage, not before and not outside of. According to the word of God which I believe completely.
Now the age for marriage. That's a different question. From my gleanings from the Bible I would say for guys when he can support one, is qualified to lead spiritually, is ready to give sacrificialy, and finally when he is ready to try to love his wife as Christ loves the church.
Suffice to say I am unmarried and do not know if I will ever be qualified. But if God works in me to bring these things about and provides a godly female then it will not be a long engagement.