By Malcolm Gladwell. (Pp 279; US$14.95.) Little, Brown and Company, January 2002. ISBN 0-349-11346-7.

The Tipping Point, first published as articles in the New Yorker and then in book form in 2000, offers a fascinating look at a concept well known to public health professionals—the epidemic. The book takes the concept a step further to examine social epidemics. In the age of AIDS and SARS, Malcolm Gladwell offers insights that might be of use in examining new epidemics, as we observe the social and health impact of epidemics on individuals, institutions, and economies. The book is never less than engaging and erudite, if occasionally a bit redundant.

Gladwell, a former science writer, has a gift for explaining the complex in clear, entertaining language. To illustrate his message he uses examples such as children’s shows, shoes, direct mail marketing, and Paul Revere’s ride. With engaging wit and a nuanced perspective he analyses exactly how and why the contagion caught and each issue became an epidemic. Public health professionals might take particular note of his views on the “epidemic” of smoking among teens and young adults.

The moment when epidemics change and reach their critical mass is called “The tipping point”, a point borrowed from epidemiology. Gladwell recognised that tipping points might happen anywhere and began to look for examples. “The best way to understand the dramatic transformation . . . or any number of the other mysterious changes that mark everyday life”, he writes “is to think of them as epidemics. Ideas and products and messages and behaviours spread just like viruses do”.

Though the book regularly refers to epidemics in the well known context, its message primarily relates to starting epidemics, not stopping them. Gladwell wants people to start “positive” epidemics of their own. He feels that the concept could work for those trying to create a change with limited resources, citing examples such as a breast cancer activist who wanted to spread knowledge and awareness of breast cancer and diabetes in a particular community. He accomplishes this by presenting a kind of blueprint for the rise of any social epidemic.

Comprehending the tipping point and its role in social epidemics involves understanding three “rules”: the law of the few, the stickiness factor, and the power of context. Gladwell contends that creating an epidemic involves a few agents of change or influential people to deliver the message. The “stickiness factor” or the change in the message that makes it more contagious or memorable can also be very powerful. Even small changes can make a difference in how a message sticks with us. Finally, the tipping point can occur in context or within the environment in which the message must thrive and spread. If the context in which a message is delivered isn’t working or tipping, change it to suit the potential contagion more effectively.

The message Gladwell imparts is essentially a positive one—in a confusing and often counterintuitive world, “tipping points are a reaffirmation of the potential for change and the power of intelligent action”. This is an idea in which all of us can take comfort.