“…A relatively large subset of the existing contributions examines the existence and features of Pigouvian taxation aimed at reducing pollution, both in monopoly and oligopoly regimes (see Bergstrom et al, 1987;Livernois, 1992, 1994;Long, 1998, 2002;and Tsur and Zemel, 2008, inter alia). Indirectly, Pigouvian taxation is also considered as a means for generating incentives towards R&D investments in environmental-friendly technologies (to this regard, see Downing and White, 1986;Milliman and Prince, 1989;Damania, 1996;Chiou and Hu, 2001; and Tsur and Zemel, 2002, inter alia). The established approach common to all of these studies consists in outlining the social optimum, where a benevolent planner chooses a production plan for the firms in the industry so as to maximise social welfare, as a benchmark against which the performance of the profit-seeking firms has to be assessed.…”