In light of recent news, this issue focuses on shale gas and fracking, with a report on the Environmental Gas Summit 2011 considering why shale gas has divided the energy industry, and an examination of whether Cuadrilla Resources’ plans for Blackpool, Preston and Southport are revolutionary or unnecessary.

Elsewhere, we look at a more economical and energy-efficient method for repairing gas pipes, a new wave of gamma-ray detector materials which could be applied to nuclear and national security, and Bristol and Oxford Universities' new centres of excellence.

We also report on a debate at the Royal Academy of Engineering about whether or not we should be concerned about the global supply of strategic materials, at which the Institute's president Jan Lewis was one of the speakers.

Features look at how heat treatment is improving the life expectancy of ball bearings, a new fluid-based heating and cooling system which could work at both ends of the heating cycle and how porous polyaniline could be used in hydrogen storage. Also, as the demand for diamonds increases, mining firm Mountain Province talk to us about Canadian diamond reserves.

Tunnelling during World War 1, North Sea oil and gas, composites and quenching are among the subjects covered by books reviewed this issue, while Material Matters ponders whether electric cars really are the solution to emissions.

As we sign off for the last time in 2011, the whole Materials World team wishes you an enjoyable festive season and New Year.