Silicones are itself a fascinating class of materials due to their unusual properties combination. One of their particularities is incompatibility with almost any organic compound and it represents one of the main problems in the expanding of the silicone field. In spite of this incompatibility but motivated by their other interesting properties, silicones are desired and tested in more and more materials where they are forced to co-exist with different partners in various systems, which exhibit a new set of characteristics. As a result, many research activities have been initiated in the last two decades on this topic. This book presents recent approaches in this direction: the use and behaviour of the silicones in hybrid systems with different organic partners.