A Second Lease on Life for Technological Forecasting THEODORE MODIS Teachers of forecasting techniques invariably discuss the Delphi method. A poi- gnant introduction to teaching this method is the following classroom experiment. Take a very thin piece of paper, such as a single layer of a Kleenex tissue, and in front of the students’ eyes fold it in half, and then in half again, and again, seven or eight times. Then pointing at the thickness of the folded tissue—barely thicker than a quarter of an inch—ask the students to estimate the thickness of 40 foldings. Discard the largest and the smallest estimates as “outliers” and average the remaining estimates. You will end up with a number between five inches and three yards, more than nine times out of ten, even if one of the students already knows the right answer, which is close to 100,000 miles, that is, halfway to the moon! And yet modern large-scale forecasting efforts, such as the UK’s Foresight Pro- grammes, are centered on the Delphi method. What happened to all the elaborate technological-forecasting techniques? Cueing technological forecasting to Kondratieff’s wave, Harold Linstone concluded that technological forecasting has already completed a life cycle, and now finds itself in a low-activity period. Invoking Kondratieff’s wave here as a tool for deeper understanding is acceptable. Today Kondratieff is no longer the discredited maverick economist he used to be during earlier decades of this century. The publication of such books as The Great Depression of 1990 [1], the stock-market crash of 1987, and the persistent worldwide economic crisis of the early 1990s have triggered a comeback for Kondratieff’s wave. Strangely enough, it is thanks to technological forecasting itself that the comeback enjoyed respect- ability. Marchetti’s work in the 1980s using logistic functions contributed to Kondratieff’s revival [2]. This time Kondratieff’s wave was established more objectively via the study of physical rather than econometric variables. Later, a new book appeared by Kondratieff himself—published by his followers—in a respectable French publishing house [3]. One quantitative determination of Kondratieff’s economic wave stipulates that worldwide economy went through a boom with apogee in 1968, went through nadirs in 1940 and again in 1996, and is due for another zenith in 2024 [4]. These peaks and THEODORE MODIS is the founder of Growth Dynamics, an organization specializing in strategic forecasting and management consulting (http://www.growth-dynamics.com) based in Geneva, Switzerland. Address correspondence to Theodore Modis, Growth Dynamics, Rue Beau Site 2, 1203 Geneva, Switzer- land; e-mail: tmodis@compuserve.com. Technological Forecasting and Social Change 62, 29–32 (1999)  1999 Elsevier Science Inc. All rights reserved. 0040-1625/99/$–see front matter 655 Avenue of the Americas, New York, NY 10010 PII S0040-1625(99)00036-0