Problem with neighbours building on our boundry?

In Legal Terms this is a Civil Matter between you and your neighbour and nothing to do with the Local Council. It will cost you money no matter what way you tackle the problem. First hire a local Structural Engineer, cost around roughly �30 per hour, get him to inspect the wall and prepare a Report saying thet it's dangerous, take photographs and write a covering letter expressing your safety concerns and give him 28 days to rectify the problem. Then send the whole package to your neighbour by Recorded Delivery and await his response. If he doesn't respond by 28 days write again saying that you are going to seek Legal Advice because it is now affecting your Business and costing you money in cancelled bookings.That should get him interested.