Moreover, there are examples of measures that worked socially advantageous in the short term but disastrous in the long term because of impairment of vital environmental functions. Arguments in support of this and some historical examples are given in the publications of Hueting and Reijnders (2004) and De Boer and Hueting for the OECD (2004) mentioned below. The theoretical and practical framework of the Sustainable national income is developed by the economist Roefie Hueting. Already in 1970 he published a collection of articles over the years 1967-1970 titled: “What is nature worth to us?” . His 1974 Ph.D. thesis was entitled “New scarcity and economic growth: More welfare through less production?” In 1969 Hueting founded the Department of Environmental Statistics at Statistics Netherlands. A multidisciplinary team of biologists, chemists, physicists, electrical engineers and economists worked for nearly forty years on the SNI and the environmental statistics on what it is based. Sustainable national income topics Environmental functions Central to the sustainable national income (SNI) is the concept of environmental function. Environmental functions are defined as the possible uses of our non-human made physical surroundings, on which humanity is entirely dependent in all its doings, whether they be producing, consuming, breathing or recreating. When use of one function is at the expense of another or the same function or threatens to be so in the future, there is competition of functions. As an illustration, once water pollutant thresholds have been exceeded, use of the function ‘dumping ground for waste’ may come to compete with the function ‘drinking water’. Competing functions are by definition scarce and consequently economic goods. Today most of the functions of our physical surroundings, which once were free goods, have become scarce goods. Transition to environmental sustainability With the present technology, population size as well as production and consumption patterns, the sustainable situation governments say they strive for cannot be reached. Given the distance to be bridged, achieving environmental sustainability will require a fairly long period. Besides many environmental measures have a time lag, sometimes of a few decades. The length of the period of the transition path to a sustainable situation is only limited by the condition that vital environmental functions must not be irreparably damaged. In view of the threat that this may happen it seems urgent to wait no longer with a change of course in the direction of sustainability. On account of the precautionary