I answered this question today and you can find this information, with live hyperlinks at www.duncanwil.co.uk/pest.html ... I have now got to discuss the limitations of PEST analysis but am finding it hard getting any info on it. Here's what I replied ... sorry but I'm pushed for time and haven't made any of the URLs into live hyperlinks: just copy and paste into your browser to do that. I started by interrogating GOOGLE worldwide for the limitations of PEST and got as many sites to do with greenfly and leaf mould as I did to do with PEST analysis. I then got rid of the limitations of part of the search and fared no better. So, I interrogated pages from the UK section of www.google.co.uk for pest analysis and here is what I think is a sample of the best that can be found there. This is a sweep through the various techniques that are discussed in the standard texts: nothing directly to do with the limitations of PEST analysis but it might spark off a train of thought. http://tbs-home.tees.ac.uk/staff/u0000514/M&S2 Wk 3 03.ppt http://www.netmba.com/strategy/pest/ begins with this "A PEST analysis is an analysis of the external macro-environment that affects all firms. P.E.S.T. is an acronym for the Political, Economic, Social, and Technological factors of the external macro-environment. Such external factors usually are beyond the firm's control and sometimes present themselves as threats. For this reason, some say that "pest" is an appropriate term for these factors. However, changes in the external environment also create new opportunities and the letters sometimes are rearranged to construct the more optimistic term of STEP analysis." and ends with this "... it may be difficult to forecast future trends with an acceptable level of accuracy. In this regard, the firm may turn to scenario planning techniques to deal with high levels of uncertainty in important macro-environmental variables." Some clues, therefore, as to what limitations we might be talking about. There's a relatively comprehensive introduction to PEST analysis here http://www.businessballs.com/pestanalysisfreetemplate.htm It also spends a lot of time comparing PEST with SWOT ... worth a read and might also spark something. IF you have the time and energy here's a real example of the application of PEST analysis http://www.mod.uk/linked_files/wsa/phase1-anx_h-i.pdf 38 pages relating to submarines being withdrawn from service. There's a hint on the potential limitations of this application of PEST analysis on page 3, paragraph 5 "... It should be noted that the costs given take no account of risk, growth, profit or VAT ..." Take a look at this http://www.marketing-intelligence.co.uk/help/Q&A/question14.htm and you will see that the final paragraph discusses some of the limitations of PEST analysis. There is also a link at the end of this page where you are invited to download a more detailed paper on PEST and SWOT analysis: you need to register in order to do that and the paper you will then be able to download is fine but nothing new. Here are two PowerPoint Presentations from Durham that relate to real cases and that again might be useful introductions to the subject: http://www.dur.ac.uk/p.j.allen/smarkets.ppt http://www.dur.ac.uk/p.j.allen/258,3,PEST Analysis The second of the above presentations is a nuisance as the author has left all of the click, click presentation gizmos in that aren’t especially web friendly … you’ll see what I mean when you get there! Happy reading and happy weekend. Hope that’s useful. DW