Thanks Woody and Tony1851,
I am doing this professionally, but am a bit clueless when it comes to PWAs.
It sounds as though both parties are likely to need to appoint surveyors, and that my client may have to agree to making a financial contribution to his neighbour in order to get his agreement...
A client wishes to extend his 'link detached' home(only the garages are connected). Neighbour has basically said 'no way'. Planning approval should not be a problem, but not sure how we can achieve a party wall agreement if the neighbour objects to my clients extension over his garage?