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Metal‐free carbon electrodes with well‐defined composition and smooth topography are prepared via sputter deposition followed by thermal treatment with inert and reactive gases. X‐ray photoelectron spectroscopy (XPS) and Raman spectroscopy show that three carbons of similar N/C content that differ in N‐site composition are thus prepared: an electrode consisting of almost exclusively graphitic‐N (N_G), an electrode with predominantly pyridinic‐N (N_P), and one with ≈1:1 N_G:N_P composition. These materials are used as model systems to investigate the activity of N‐doped carbons in the oxygen reduction reaction (ORR) using voltammetry. Results show that selectivity toward 4e‐reduction of O₂ is strongly influenced by the N_G/N_P site composition, with the material possessing nearly uniform N_G/N_P composition being the only one yielding a 4e‐reduction. Computational studies on model graphene clusters are …