When we look at the whole system, the whole waste management system, there are different types of those. We can talk about, for example, an in-house waste management system. This may be particularly relevant for industries where they use part of their waste from some part of the production as, for other purposes within the same industry. Maybe this could be, in some cases, where we have some wood waste left over wood and this is used for heating purposes within the industry. And so this is an example of an in-house waste management system. Another type is an unmanned system, and this is what we often see along roads, highways, may be in nature, where people just have thrown away their waste where they were not supposed to put it. But this happens, of course, and this is essentially littering. And this is something which, in most cases this is not warranted. But this is also a type of management system. Essentially the options for people are not provided, so they have to get rid of their waste in other ways. A third type is return systems. This may be specifically for individual types of product. It can be beverage cans, for example, or containers, plastic containers for beverages that are, that we have a deposit on, and people return them to the shop, get their deposit back. And then the bottles go directly back to the producer, that can recycle them. So there we have sort of a closed loop, where the waste goes directly back to the producer. So this is another type of system. Then we have the municipal solid waste system and this is what we often discuss when we talk about how to handle waste in society. This represents the waste that comes from households, from us, from small industries, small shops for example, but not larger industries. Usually large companies, large industries with specific types of waste, they have their own contractors coming and collecting their waste and then delivering that to the receiving facilities. Whether this is a landfill or this is a special waste facility, or waste incinerator, or recycling facility, or whatever it is. This is also the industry waste. This is a specific waste management system also. Another type is hazardous waste. In many countries, there are special regulations for hazardous waste, and this has to be handled specifically. Because we are concerned about pollution and concerned about working health environment, related to handling the hazardous waste. The clinical waste that we looked at earlier, this was an example of hazardous waste that has to be collected specifically and is sent to a specific treatment facility. So this is also a special subsystem. When we talk about regulation of waste handling in many societies, there are different levels also. On one hand we can have a federal level that regulates the overall, maybe targets, recycling targets, for example, or overall framework for ending the waste. The U.S. is one example, E.U. is another example where there are some, in the European case, an E.U. wide regulation, that directive that states how the overall waste management should be in the individual member states. Then in Europe, again, each country, they have to implement these oil regulations. They have to define how the countrywide, the national implementation is. What are the the specific limit values perhaps. Where can the facilities be located? How should the local organizational waste management be handled? In many cases also, then, we have a very local level. This can be at municipality level, where In Denmark, for example, we have the municipalities taking care of the local system for households. They provide the local guidelines for sorting the waste. What we looked at here, what kinds of individual materials the waste should be sorted into, which type of containers it should be put into and so forth, how this should be organized. So there are these different levels. On top of all this, there may also be some international regulations. There can be some conventions, for example, that regulates what we do between countries and regions of the world with waste. The Basel Convention is one example which set limits on how we can export hazardous waste. We're not supposed to, for example, just collect some hazardous, problematic waste and then export it to some other countries, and then let them deal with the problem. We should take care of our own problems in relation to waste. And this is what this convention tried to make sure that this happens in the right way.