Local planning authorities are required to have policies in their development plans which protect SSSIs. They are then required to consult the appropriate conservation body over planning applications which might affect the interest of an SSSI (such a development might not be within or even close to the SSSI itself). The effect of this is to prevent development which harms the interest – except where the value of that interest is over-ridden by some more important factor, for example a requirement for a major road or port or oil pipe. The requirement for consultation covers any development which might affect the interest, not just developments within the SSSI itself – for example, a development a long way upstream of a wetland SSSI might require consultation. Note that some developments might be neutral or beneficial, even if they are within the SSSI itself – the critical point is whether they harm the interest features.