Four Leaf is an eco-label but not in the traditional sense as defined by the ISO. We focus on the Greek definition of eco - oikos, being the common derivative in both economics and ecology. The ability to quantify environmental friendliness in an economically viable way is the core of the Four Leaf system.

Key to Four Leaf's success is that data required from suppliers is easily available and known.  It can be compiled by Financial Departments without great burden or expense to manufacturers.

Four Leaf has identified four main environmental factors against which products or services and their suppliers are rated. These are the three inputs of raw materials, energy consumption, water usage and the output of emissions. Each of these factors correlate to a specific leaf quadrant when the rating is visually presented to consumers. The Raw Materials leaf relates only to the individual product. All others rate the total performance of the manufacturer to ensure inclusion of the head office footprint and to avoid skewing results due to the use of differing proportioning methodologies.

Manufacturers answer a total of 20 questions relating to their environmental efficiencies. The answers to each of these questions are weighted relative to their total impact within their specific leaf. For example, in the Water Leaf, the change in fresh water consumption over time contributes half of the total score, whist 30% is attributed to the percentage usage of recycled/reused water and the remaining 20% is allocated to the upstream utilisation of water.

There is precedent for a Four Leaf rating system. In March 2007, Britain's Carbon Trust announced a pilot programme for its Carbon Label. This label utilizes lifecycle assessment to provide the CO2-e by product. In September of that year,Tesco's became a pilot partner. The Carbon Reduction label, which concentrates on one area of the envirornment only, is slowly being rolled out to differing global markets, including Australia from 2010.  Uptake of this label is however slow due to the process involved in acquiring independent verification of greenhouse emissions for the entire lifecycle of each product.  Planet Ark, responsible for the Australian roll-out, is quoted as forecasting only 5-10% of supermarket products carrying the label within 5 years.  

In September 2007, on the other side of the Atlantic, Wal-Mart launched a trial programme with 30 manufacturers to capture data relating to their carbon footprint. This was a further step in their environment programme which included the 2006 introduction of an online packaging modeling system, now mandatory for all suppliers. From 2008, Wal-Mart buyers received a rating of suppliers in accordance with their scorecard, with preferred suppliers at the top of the list and low performers at risk of losing supplier status. Buyer incentives are now linked to the system to provide additional incentive to range products with environmentally friendly packaging.

Whilst excellent incentives, both the Carbon Reduction label and Walmart initiatives concentrate on only one area of environmental degradation whilst also time and cost intensive.