There's a saying that imitation is the ultimate form of flattery, but in the realm of hip-hop, such a practice can be frowned upon in many instances. A cosign, however, is considered to be the highest compliment an artist can get, particularly when it comes from another artist of a particular respect or stature. Being that the rap game is so competitive and driven by ego and bravado, paying homage and uplifting another artist is humility at its finest and a sign of mutual respect, thus doing their part to improve the culture and ensure cream rises to the top.

Many artists have given out cosigns over the years, but there's a list of rappers that have gone one step further and introduced new talent to the big stage. Already in the midst of their own careers and have established themselves as stars in their own right, they've reached back and added to the fabric of hip-hop with their discoveries, strengthening their legacies in the process.

From Fat Joe to Queen Latifah, The Boombox looks back at fifteen instances throughout rap history in which a legendary rapper put on another legend in the name of paying it forward.