One of the London Olympics' sustainability goals is to send zero waste to landfill, and though that may seen like a daunting task -- 2.1 million spectators attended in the first three days -- it's little different than a company going zero waste.

"The bulk of the Games' operation waste tends to be food and food packaging, and the vast bulk of it comes from spectators," said David Stubbs, head of sustainability efforts at the 2012 London Olympic Games.

Although types of waste differ from company to company or event to event, some key factors remain the same: control and communication.

For the Olympics, that came down to controlling what materials are brought in and what packaging and items are used on the grounds.

As for what packaging spectators bring in, that intersects with security, which only allows liquids in containers up to 100 ml (about 3 ounce), essentially keeping out any normal-sized plastic, aluminum or glass packaging. Relatedly, the zero waste goal is for "closed venues," leaving out areas like cycling courses where anyone is free to come and observe.

To control what waste gets produced within the grounds of the Games, the London 2012 Organizing Committee worked with all caterers on site to make sure they used the same supplier for compostable materials.

That means all plates, cups, cutlery and packaging can be composted, and since they all come from the same place, they all meet the same standards.

Next page: Extending the coding system beyond the games