In the period since the First World War the importance of the cities has been reinforced through a rapid expansion of their tertiary functions combined with retention of an important stake in manufacturing, albeit with much diversification. The accessibility of cities has improved through a rapid growth in road transport offering a far more developed system than the railway network, which has been drastically reduced in consequence. This has meant the avoidance of a ‘dual economy’ type of development in which city growth is associated with increasing urban isolation and diminishing influence or contagion throughout the region. But it has, equally, not induced urban growth evenly throughout Scotland: disorderly urban sprawl would not be possible anyway given the relatively stringent planning controls that have evolved during the period but even in the context of government and local authority control of urban layouts it is evident that the growth areas are restricted, especially in the Outer Regions where the urban network remains poorly developed. Thriving industries require the full range of urban amenities such as may usually be found in the regional centres of Scotland, but spread away from these cities is difficult. For an industry can only flourish in the context of favourable environmental circumstances. The spread of industry to the Outer Regions is socially necessary, in view of the reduction in employment in primary sectors which are no longer so labour intensive, but the recent improvements in terms of power and transport are not balanced by a satisfactory urban pattern.