John Kay

The return on your portfolio is the aggregate of the returns on individual securities: the risk on your portfolio is not the aggregate of the risk of individual securities. With the aid of diversification you can earn more return with less risk.

Having seen off the taxman, you must see off the sharks of the financial services industry.

The decline of GM is as instructive as its rise. The challenge of how to reconcile professional management with a culture of innovation remains for ever a central issue for management thinkers.

When the future arrived in 2007, we learnt that others had febezzled from us on a massive scale. And that we had also febezzled from ourselves.

Diversification is a matter of judgment not statistics. A model will tell you only what you have already told the model and can never replace, though it can enhance, an understanding of market psychology and the factors that make for successful business.

John returns to his experience as a Halifax director to retrace the rocky road to last week’s rescue takeover.

On the last of these comments on the UK fiscal framework John considers the impact and role of borrowing limits

If we are persistently irrational, perhaps the behaviour is not irrational.

A report to CE International plc (formerly the Church of England) on the management challenges it faces.

To celebrate the 100th anniversary of our successful escape from extinction by the Tunguska meteorite, John examines the economics of the end of the world.