Each of us can make a positive difference to the world with what we do every day. Here is an inspiring little book giving ideas on how this can be done.

Tony Ryan, a conference presenter based in Queensland, has written "The Ripple Effect: how you can make a difference to the world every day".

Ryan records how a female friend of his noticed a distraught young mother nursing a crying baby at a shopping centre cafeteria. His friend bought her a cup of tea, presented it to the mother, and offered to nurse the baby for a few minutes. A little later, both mother and baby had calmed down. The young mother thanked her for her efforts, they parted and did not see one another again. End of story? Not quite.

Several weeks later, a letter appeared in the local newspaper written by the young mother. She explained that she had been crying because she had planned suicide and did not know what to do with her baby. However, the single action by Ryan's friend had been enough to boost her into positive action and, since the time in the cafeteria, she had managed to create new purposes in her life. She and the baby were now doing well.

This is a good example of the "ripple effect". The book goes on to set out many examples of how a person can create their own ripple effect.

For example, a person is in a lunchtime queue at a snack bar. It is a long queue and people are becoming impatient with the delay. Ryan recommends smiling at the shop person and thanking her for creating such excellent food, and making sure that other customers hear you. The ripple effect: the shop person, who has been overwhelmed by negative comments, is now re-energized by the positive words; she chats and jokes with the next customer, who happens to be embroiled in an ongoing dispute in her own office; that customer goes back to the office with a more positive approach to that office problem. Not a bad result from just a few positive words.

Of course, there can also be negative ripple effects, where people actually make a situation worse. One of Ryan's examples comes from Victoria's railways where many station ticket sellers were replaced with automatic ticket machines to save money. However vandals discovered how to break into those unsupervised machines. Expensive security guards were then hired to patrol the railway stations. The final cost was far in excess of maintaining the original ticket-sellers at the stations.

Ryan also records the example of the ripple effect from the World Health Organization (WHO). In the early 1950s, the island of Borneo was ravaged by a malaria plague. The WHO sprayed the entire island with DDT to eradicate the mosquitos carrying the disease. The spraying was successful and the incidence of malaria dropped.

But soon after, the thatched roofs of the islanders' huts began collapsing because the DDT had also killed the wasps that ate the thatch-eating caterpillars, allowing the caterpillars to multiply. (The authorities responded by providing corrugated metal roofs - but this made for noisy nights when the monsoon rains poured down).

The DDT also built up through the food chain, from insects to lizards and even to cats. As the cats died out, the rat population increased. The rats then created an outbreak of sylvatic plague and typhus, and the WHO finally had to parachute in live cats to Borneo to redress the balance.

In short: buy the book and learn how to send out positive ripples. Every action a person makes creates positive or negative ripples. Be aware of the ripple effect and make sure that you are creating positive ones.

Broadcast Friday 8th August 2003 on Radio 2GB's "Brian Wilshire Programme" at 9pm