A dispersion flattened non-zero dispersion shifted optical waveguide fiber which includes a central core region surrounded by an outer cladding region, the central core region having an alpha less than 4. The optical fiber has a dispersion at a wavelength of about 1550 nm of between about 4 ps/nm/km and about 8 ps/nm/km, and a dispersion slope of less than 0.025 ps/nm2/km at every wavelength between about 1525 nm and 1650 nm.