The global phenomenon of urbanisation from the beginning of industrialisation to the present day has brought opportunity and prosperity, albeit at a cost in the quality of life. With an increasing city population, the complexity of the challenges also increases, the causes and solutions for this are outlined below.
The causes for the decrease in the quality of life are paradoxically the prosperity endowed on such metropolitan centres. Their growth is largely due to the increase of opportunities on offer, which in turn increases their attractiveness, essentially they are trapped in a positive self-reinforcing cycle. However, this eventually leads to a decrease in the quality of life as the city can experience overcrowding, exorbitant property prices, and increased vulnerability to terrorist attacks. For example the density of London makes it a more efficient place to attack, when compared to a smaller city such as Bradford. Therefore, due to continuous growth and prosperity, urban citizens, especially the less well off, often experience a lower standard of living.
Considering the solutions, greater investment in public transport would ease traffic congestion, as would bike lanes. In theory this would reduce air pollution, and possibly improve the wellbeing of the population if they did adopt a more active lifestyle and cycle to work. To counter violent terrorist attacks, cities could embark on CCTV installations, so as to closely monitor for threats. For example, it is said, the CCTV in London has foiled many potential attacks, and therefore greatly increased the security of its citizens.
To conclude, a wealthy city attracts a large population inflow, which then causes pressure on existing infrastructure and security. Various solutions exist to mitigate such drawbacks, nevertheless an indefinite solution has yet to be found. 
The global phenomenon of  
urbanisation
 from the beginning of  
industrialisation
 to the present day has brought opportunity and prosperity, albeit at a cost in the quality of life. With an increasing city population, the complexity of the challenges  
also
 increases, the causes and  
solutions
 for this  
are outlined
 below.
The causes for the decrease in the quality of life are  
paradoxically
 the prosperity endowed on such metropolitan  
centres
. Their growth is  
largely
 due to the increase of opportunities on offer, which in turn increases their attractiveness,  
essentially
 they  
are trapped
 in a  
positive
 self-reinforcing cycle.  
However
, this  
eventually
 leads to a decrease in the quality of life as the city can experience overcrowding, exorbitant property prices, and increased vulnerability to terrorist  
attacks
.  
For example
 the density of London  
makes
 it a more efficient place to  
attack
, when compared to a smaller city such as Bradford.  
Therefore
, due to continuous growth and prosperity, urban citizens,  
especially
 the less well off,  
often
 experience a lower standard of living.
Considering the  
solutions
, greater investment in public transport would  
ease
 traffic congestion, as would bike lanes. In theory this would  
reduce
 air pollution, and  
possibly
  improve
 the  
wellbeing
 of the population if they did adopt a more active lifestyle and cycle to work. To counter violent terrorist  
attacks
,  
cities
 could embark on CCTV installations,  
so as to
  closely
 monitor for threats.  
For example
, it  
is said
, the CCTV in London has foiled  
many
 potential  
attacks
, and  
therefore
  greatly
 increased the security of its citizens. 
To conclude
, a wealthy city attracts a large population inflow, which then causes pressure on existing infrastructure and security. Various  
solutions
 exist to mitigate such drawbacks,  
nevertheless
 an indefinite  
solution
 has  
yet
 to  
be found
.