In this investigation we study the environment of flat galaxies. Flat (or superthin) galaxies are late-type edge-on spiral systems that exhibit large axial ratios, small stellar disk scale heights and no distinct spheroidal bulge component. This type of galaxy appears to be a pure disk system with an extended blue stellar disk probably embedded in a thick red layer. Flat galaxies are very common objects with low star formation rates, low metallicities, low optical surface brightness but high neutral gas fractions. Their rotation curves resemble those of dwarf and irregular galaxies. These simple disk systems offer the unique opportunity to constrain galaxy disk evolution in underevolved galaxies in the nearby Universe. They are also an evolutionary puzzle since merger scenarios do not predict the formation of pure disks. Using the Sloan Digital Sky Survey, we have compiled a complete sample of flat galaxies covering an area of 2099 square degrees. We are using this sample to study the colors and morphological parameters of these objects, to investigate their environment and to study possible interrelations.