Robert B. Cialdini's book - Influence: The Psychology of Persuasion is a good read. The consistently underhanded techniques of car salespeople and evangelists for one or other faiths is entertaining, enlightening and extremely useful in terms of knowing the sorts of tactics employed by sales, marketing and a host of other people trying to get you to do something they want.
However, its not that much use for this project manager other than gaming* members of the project team on who's turn it is to make the tea round.
* One of those verbalised words becoming increasingly popular. However, links to game theory and a constant reminder that complexity manifests unintended consequences means the author has a ticket for this bandwagon.
Typically I have fallen back on the techniques learned in the field of service delivery. Equally I have had the wonderful opportunity to see just how powerful presenting stakeholders with new and better information can be. Don't ever underestimate the potency of this very simple approach. And while we're at it, don't ever confuse simple with easy!
By pure luck (a lot more on this in the future) I was fortunate enough to attend a talk run by the excellent APM on the subject of Influence. This was an hour long distillation of some of the key points contained in the book Influencer: The Power to Change Anything - a deservedly bold title with too many authors to include here easily.
I'm not going to seek to reproduce precisely what the book encompasses, but I will include the illustration below which I think is certainly a core principal.
I've used here the simple example of encouraging cycle helmet use amongst cycle commuters. The book's authors, backed by a bibliography longer than is typical, contend that people don't do things because they either can't or don't want to and do things because they can and they want to.
Straight away, I think there's an interesting observation to be made right there - people only need one box ticked not to do something, but both boxes ticked to do anything.
Next, the book's authors identify three domains in which these motivations can arise, the personal (you), the interpersonal (peer pressure) and environmental (what's sitting in the immediate vicinity).
Supplemental to this having been proven to be a very effective approach, it is a wholly defensible and legitimate strategy to employ with stakeholders, one that can be documented and one even that the customer will find it difficult to find fault with.
The book elaborates some remarkable success stories using this approach. It makes the point that you only need to 'tick' four out of the possible six boxes in order to stand a very great chance of success.
Again, the dimension of proportionality must be considered, but if you need to reposition stakeholders and this is critical to your project's success, then I contend there are few better approaches.