A simple method for the preparation of block copolymers by a two-step sequential Type II photoinitiation is described. In the first step, amine functionalized poly(methyl methacrylate) (PMMA-N(Et)(2)) is prepared by photopolymerization of methyl methacrylate at = 350 nm using benzophenone and triethyl amine as photosensitizer and hydrogen donor, respectively. Subsequent benzophenone-sensitized photopolymerization of tert-butyl acrylate using PMMA-N(Et)(2) as hydrogen donor yielded poly(methyl methacrylate)-block-poly(tert-butyl acrylate). The obtained hydrophobic block copolymer is readily converted to amphiphilic polymer by hydrolysis of the tert-butyl ester moieties of the block copolymer as demonstrated by contact angle measurements. All polymers are characterized by NMR, Fourier transform infrared and UV-vis spectroscopies, and differential scanning calorimetry (DSC) thermal analyses.