I was interested to read your article “Jolly green clients” (21 July, page 44), which highlighted the bewilderment that still surrounds the term “sustainability”.

It is not surprising that people are confused by it when other words such as “green”, “energy efficiency” and “CO2 emissions” are bandied about with little regard to their

true meaning. The Oxford English Dictionary gives definitions for the word sustain as:

“1 To strengthen or support something; 2 to bear the weight of something; 3 to keep something going over time; or 4 to suffer something unpleasant.” Until fairly recently, most people seem to have been split between numbers three and four.

Nowadays, number three is the most popular definition, and I believe the key to keeping something going over time is collaboration. We must work together from the concept stage to examine everything that produces the environmental impact of a new or refurbished building. This responsibility falls on everybody involved in the project. Once we have identified the elements, we can then go about finding the most suitable and cost-effective way to deal with them.

Doug Hillman, RLF London