Final Activity Report Summary - HYBRIDMAT (Novel Ordered Micro and Mesoporous Organic-Inorganic Hybrid Materials with Crystalline Structure) The main scientific objective achieved developing the present project was the preparation of ordered porous materials whose polymeric framework is composed of both inorganic and organic fragments. With this objective, bridged organosiloxane precursors were used as a silica source in the synthesis of hybrid materials to incorporate organic groups directly into the framework of the pore walls instead of grafting these organic species onto the pore wall surface. It was possible to obtain hybrid organic-inorganic zeolitic materials using different templates as structural direct agents (SDA), instead of surfactants, to synthesise microporous solids with the characteristic advantages of zeolites. Different types of microporous hybrid organic-inorganic materials with ITQ-21, MFI and BEA structures were synthesized from bridged organosiloxane precursors as silica sources. The organozeolites prepared contain the highest number of methylene and ethylene groups known up to now (9per cent wt of carbon), into their typical inorganic frameworks, while maintaining high porosity and free porous volume. This effect is very marked in the organozeolites with Beta topology. Characterisation techniques show that the type of structure finally crystallised and the crystallinity achieved are key parameters to introduce high carbon content into the zeolitic frameworks. The hybrid organic-inorganic materials synthesised, with incipient structuration level, present the conventional morphology and textural properties of zeolitic materials. The hybrid materials obtained could be highly innovative, because their ability to incorporate a large variety of bridging organic species making possible to generate new materials with interesting mechanical, electronic, optical and magnetic properties, as well as in the area related with the storage (H2) or separation (CO2) of gas, catalysis, and as hosts for nanoclusters synthesis. Definitively, these novel materials combine the structural characteristics of ordered porous silica with the chemical functionality of organic polymers.