Book excerpt: Silicon Based Polymers presents highlights in advanced research and technological innovations using macromolecular organosilicon compounds and systems, as presented in the 2007 ISPO congress. Silicon-containing materials and polymers are used all over the world and in a variety of industries, domestic products and high technology applications. Among them, silicones are certainly the most well–known, however there are still new properties discovered and preparative processes developed all the time, therefore adding to their potential. Less known, but in preparation for the future, are other silicon containing-polymers which are now close to maturity and in fact some are already available like polysilsesquioxanes and polysilanes. All these silicon based materials can adopt very different structures like chains, dendrimers, hyperbranched and networks, physical and chemical gels. The result is a vast array of materials with applications in various areas such as optics, electronics, ionic electrolytes, liquid crystals, biomaterials, ceramics and concrete, paints and coatings ... all needed to face the environmental, energetical and technological issues of today. Some industrial aspects of the applications of these materials will also be presented.