Since the publication of Martin Weitzman’s famous paper (1974) which compared price- and quantity-based instruments, economists have been deliberating when marketable permits (a quantity instrument) are better than Pigouvian taxes (a price instrument). Theoretically, these are equivalent. However, Weitzman noted that this equivalence is true in a world of perfect information only: in a world where all agents are perfectly informed about anything they do. There is no such comfort in environmental protection policy. When deciding on a cap or on a Pigouvian tax rate, authorities can err and miscalculate the costs and benefits affecting the interested parties, i.e. firms and their neighbourhoods.