The event was very successful in raising a good pile of dough, thanks largely to the enthusiasm and organisational skill of our administrator, Kelly.

It was also successful because of the goodwill generated among the workers in our building who attended.

These workers - from about 20 firms and agencies - see each other on a daily basis, but only as we shuffle in and out of the lifts, mostly averting our eyes, having no personal contact beyond an occasional nod or "good morning" grunt.

At the morning tea, though, the same people expressed delight that they were able to meet their work-neighbours, find out things about each other, and share the pleasure of a tea-room table laden with goodies and the chance to contribute to an important cause.

"Let's make sure we do it again," was a universal farewell.

Our building is only seven storeys high, built sometime in the 1980s.

But it is a good case study of the modern office.

Modern office buildings emerged in the late nineteenth century as a result of four inventions.

First, the use of steel girders instead of masonry enabled building heights to soar.

Second, the invention of the lift, or elevator, gave workers access to floors many storeys above the ground.

Third, air-conditioning enabled office work to take place in controlled conditions all year round.

And, fourth, the invention of internal telephone switchboards enabled workers to communicate efficiently even though they were separated by office partitions and floor plates.

These inventions meant firms and government agencies could concentrate teams of workers in prime central business districts.

Recently I visited Philadelphia and saw the world's first air-conditioned tall building, the Philadelphia Savings Funds Building, now the Loews Hotel; and the world's first building with an internal telephone system, the American Telegraph and Telephone Bourse Building.

It's amazing how in human history inventions concentrate in particular places.

Yet it's funny how humans invented a way of clustering workers into small geographical areas but in doing so increased their isolation from each other.

Funny, too, how a simple gesture such as the offer of a cuppa and a cup cake and a chance to contribute to a common cause, can bring isolated office workers together in a humane, friendly way.

Phillip O'Neill is Professor and Director of the Urban Research Centre at the University of Western Sydney.