The key of the C2C principle lies in the concept:waste is food. In other words; there is no wast. All used materials should, afther there life as one product, be able to be profitable applied in an other product. This cycle is than compleet...waste becomes food.

There are two cycles: 
the biological and the tecnical cycle. 

I stick as much as I can to the biological cycle but also keep an eye on the technical cycle of products that I use in my designs, regarding production methods, disassembling and up-cycling.

The three basic rules of Cradle to Cradle are:

Waste is food
The sun as energysource
Respect for diversity