The term PESTLE has been used regularly in the last 10 years and its true history is difficult to establish.
The earliest know reference to tools and techniques for ‘scanning the business environment’ is by Francis J. Aguilar1 who discusses ‘ETPS’ - a mnemonic for the four sectors of his taxonomy of the environment: Economic, Technical, Political, and Social.
Shortly after its publication, Arnold Brown for the Institute of Life Insurance (in the US) reorganized it as ‘STEP’ (Strategic Trend Evaluation Process) as a way to organise the results of his environmental scanning.
Thereafter, this ‘macro external environment analysis’, or ‘environmental scanning for change’, was modified yet again to become a so-called STEPE analysis (the Social, Technical, Economic, Political, and Ecological taxonomies).
In the 1980s, several other authors including Fahey, Narayanan, Morrison, Renfro, Boucher, Mecca and Porter included variations of the taxonomy classifications in a variety of orders: PEST, PESTLE, STEEPLE etc. Why the slightly negative connotations of PEST have proven to be more popular than STEP is not known. Some purists claim that STEP or PEST still contain headings which are appropriate for all situations, other claim that the additional breakdown of some factors to help individuals and teams undertaking an environmental scan.