Trains leaving Kings Cross Station. Photographer: Graham Turner

As though returning to work after the Christmas break wasn't enough to lower the spirits of the nation's commuters this morning, they also had to face another rise in rail fares. On many lines this increase will mark the fourth successive year that ticket prices have risen above the rate of inflation. The Tories have said that these increases are a sign that the government's 10-year plan to improve the railways has failed.

Train companies have assured the public that the money will go towards improvements to rail services, but critics have offered other theories. The shadow transport secretary, Chris Grayling, has claimed that the government and rail companies are using higher fares to discourage commuters and reduce overcrowding on peak-time services. A spokesperson from the department for transport denied the allegations, saying, "Ministers have consistently said that they want the railways to grow and passenger numbers to increase and will be publishing later this year a framework for the longer-term future of the railways."

What do you think - should people be willing to pay higher prices, or are they simply a way of reducing pressure on a rail network suffering from chronic underinvestment?