Type-H core/shell quantum dots are characterized by a staggered alignment of conduction and valence bands (see Figure), giving rise to a broad tunability of absorption and emission wavelengths. Colloidal ZnTe/CdE (E = S, Se, Te) core/shell quantum dots have been prepared with emission quantum yields of up to 30%. The synthesis route presented should be applicable to other type-II core/shell quantum dots.