Targeting fuel refiners and importers: influencing fuel supply. Measures to influence fuel supply might involve subsidies and transfers for research, development and deployment, or regulations and standards for fuel quality. Such standards are most effective when they regulate performance criteria, rather than fuel composition per se. Targeting developers and planners: influencing the built environment. Urban form and design can influence how long average trips taken in urban areas need to be, and what modes of transport are viable. While formal land-use control or planning/zoning regulations are often the most.
