Firstly, there was a change of government, which some readers may be too young to remember. Older planners, however, may wish to celebrate or lament the memory before continuing.
The new environment minister was Michael Heseltine and he paid a visit to the Town and Country Planning Summer School on 13 September to set out his ideas on the planning system. In those days this was a big event.
Nowadays it is hard to attend any half-decent conference without hearing from the current planning minister, but back then ministers were far less inclined to venture out to speak to the likes of us.
I remember it well because I drove him from York station to the university.
The time of his speech had changed twice during the morning - something to do with a cabinet meeting. This presented us with an organisational challenge with which we dealt superbly, demonstrating the flexibility of the planning profession in a practical way.
The speech was generally regarded as being hostile to planning. But although trenchant in places, it was not particularly aggressive, except for the passage about "thousands of jobs locked away in the filing trays of planning departments". The remark raised hackles then and probably still does.
I always think of the tens of thousands locked away in planning permissions that have been granted but never implemented.
Otherwise, much of the speech could have been given at this year's summer school. Heseltine wanted a system that was "efficient, responsive and speedy". He deplored the fact that only 70 per cent of applications were decided within eight weeks: "This cannot be right." He wanted more pre-application discussions and more delegation. He believed in targets.
Heseltine promised to speed up appeals, which, it seems, were taking a long time. He also called for plans to be produced more quickly. But unlike deputy prime minister John Prescott - and unlike most readers, I guess - he wanted less involvement by planners in design issues and expressed distaste for regional planning. So it was not all good news.
The other thing that happened in September 1979 was the publication of The Grotton Papers. If I do not mention this great anniversary, then I suppose nobody else will, except perhaps my co-writers Steve Ankers and David Kaiserman. The book was a satirical look at planning and was described at the time as "a work of genius" by its authors. I think it was funnier than the Heseltine speech. In some ways, in my more optimistic moments, I like to think that it was almost as influential.