Preferential sequestering of surface modified metal/semiconductor nanocrystals within microphase separated block copolymer domains holds the promise for engineering large-scale polymer based photonic materials. In my talk I want to review block copolymers as a material platform for photonic crystal engineering as well as the prospects of metallodielectric photonic materials based on metal nanocrystal/block copolymer composites. The effect of metal nanocrystal additives on the optical properties of the composite is found to be determined by: (1) changes in the optical properties of individual nanocrystals due to the spatial confinement of the free electrons by the crystal boundary and (2) by collective effects resulting from the particle size-dependent morphology of the nanocrystals within the polymer domains. The particle core size, the polymer domain spacing as well as the particle surface chemistry are shown to determine three distinct morphological types in particle/block copolymer composites. A detailed comparison between morphological studies and theoretical predictions will be presented that aim to better understand and control morphologies of structured cluster matter in order to tailor optical and mechanical properties of new photonic materials.