Suburbanisation = is the decentralisation of people, employment, and services from the inner city towards the rural urban fringe.
One effect is that the affluent middle class often move to the suburbs where the houses and quality of life are generally better - 'white flight'. On one hand this is positive as the suburban areas will thrive with its wealthier inhabitants (gentrification). However the inner city will see negative consequences as the inhabitants remaining tend to be poorer and often foreign immigrants which can lead to both economic and ethnic segregation.
Another effect of suburbanisation is that over time transport links have been significantly improved to a high standard. For example a train from Surbiton into London Waterloo takes 18 minutes making living in a suburb and working in the inner city an easy and viable option. This is a positive for both suburbs and transport advancement alike as they both aided and were dependent on each others advancement. However this has hugely increased the amount of commuters travelling far to get to London which has disastrous impacts on the environment.