<para> Theory-inspired design of organic electro-optic materials is explored for three classes of materials: 1) chromophore/polymer composites; 2) chromophores covalently incorporated into polymers, dendrimers, and dendronized polymers; and 3) chromophores doped into chromophore-containing host materials. Correlated quantum/statistical mechanical calculations are used to quantitatively simulate electro-optic activity for a variety of materials falling into these three classes, elucidating the dependence of electro-optic activity on chromophore dipole moment, chromophore shape, covalent bond potentials, and dielectric permittivity. The practical consequence has been the production of materials exhibiting femtosecond response electro-optic activity approaching 600 pm/V at telecommunication wavelengths. Theory also provides insight into minimizing optical loss and maximizing stability. </para>