Over the last century, the changes in the consuming habits have brought a dramatic increase in the quantity of waste produced by households. When waste had always been dumped without much questioning in the past, our developed societies suddenly realised that the carrying capacity of the "spaceship earth" was limited.

Therefrom, different treatment options were developed to reduce the volume of waste destined for dumping : incineration, re-use, recycling, composting. However, there appears to be many differences in the choice between the treatment options from one country to another.

The first part of the paper is dedicated to the presentation of the waste management policies implemented by different countries. Historical and geographical factors usually explained in each country the prevalence of a treatment option over the others. But new factors (ecological, temporal and financial) have now brought a change into the traditional system of waste management.

In the second part of the paper, a global approach is used to estimate the real costs of the different treatment options. The presence of positive and negative externalities, usually not included in the decision-making process, can induce some important difference between the cost of a treatment option borne by a local district (private cost) and the cost borne by the whole community (social cost).

In our paper, we show that some decisions made today are not flawless in the long run. With a legislative process currently taking place in most countries to set up the rules for a sustainable waste management system, it is urgent for economists to help the public authorities by assessing the treatment options from this global viewpoint.