The Author's method of evaluating a natural park system is based on that devised and used some 10 years ago by the National Park Service of the USA (i.e. exactly a century after the institution of the first national park of that country and of the world, Yellowstone). In the American evaluation of 1972, serious gaps and inadequacies were identified in the national park system of the USA, which until then did not grow as a ‘system’ but rather as an aggregation. However, that system and its features are not described or commented on, but only the method itself is described.

Then the method is applied to a much smaller (Italian) region—Piedmont—in which the ‘natural parks and reserves system’ has only recently been planned and is beginning to be set up—generally with good individual choices, but apparently without any other sound criterion. The Author finds that the method is still meaningful and useful and, after a brief description of Piedmont in so far as the method requires it, he expounds his main conclusions about the inadequacies of the system and the possible remedies.

Finally, the method is briefly examined in a general way and some remarks are made about it, in order to point out its main merits, which are its synthesizing capacity and its simplicity: so appealing are they, that it is felt necessary to give some warnings about its limitations, which include lack of consideration of sizes of areas, their number, and their distribution.