Integrated Buildings & Structures

I am a practicing civil engineer since 1965 and am interested in sustainability very much. But I still need to understand in what way the term 'sustainability' affects my profession, as I work as a consultant, catering to different clients in different ways, from design/ drawings to construction management, from small scale to large projects!
i am totally dependent on the fees that I receive in return. So what should sustainability mean to me?

I agree with John Turner.  Civil Engineers have always built sustainable structures if sustainability means something that lasts. Unfortunately, sustainability in this context means energy supplies.  John is correct when he says that todays buildings cost more to construct, more to operate and do not affect in a significant way energy use.  In my practice that the types of building envelopes that are used today because they are more sustainable for energy do not hold up to the forces of nature.  Much of what I do relates to moisture intrusion.  These lighter weight system are too flexible, must be precisely installed to function and once breached are very costly to repair.  I have also seen that even if you start out to build a sustainable building, there is no guarantee that you will actually get one.  There are too many variables in the deign and construction efforts that can cause a building to bleed certified.  Millions of dollars have been spent in these attempts to build a "perfect building".  Worse yet are the 10's of millions of dollars spent on litigation because he building do not function properly  After all what is a building's function?  Is it not to protect whatever is going inside it from the weather?  This whole climate change/global/warming debate has caused out profession to loose it's way.  So I end this post with one question.  How does a gas that is .32% of the atmosphere,heavier than air and water soluble have such a devastating impact on the planet?