You cannot force your neighbour to do any of the above. I suggest that you politely ask her if the tree can be pruned or removed.

I agree with Kildermorie. It sounds like you would like the tree reduced in height as it causes you so much frustration. Is it worth suggesting to your neighbour that you will share the cost of having it reduced in height by a tree surgeon? Just a thought.

I am surrounded by trees and some are much taller than mine and I find leaves come from all over when the wind blows. I expect masses of leaves this time of year and harvest them for leaf mould. I dont think you would find any help in trying to force her to come around and clear your leaves, but if the tree was proving to be a danger to your property that may be different! My advice is forget it and get a leaf hoover.

I hope my new neighbours don't feel the way you do Aoharny, because a fair amount of leaves from our red oak do land in their garden. When I had it pruned two years ago all my neighbours said they liked the tree and the autumn leaves were just the price paid for having beautiful trees to enjoy.
I get masses of sycamore leaves from the next garden and I wouldn't dream of complaining, although I don't use those for leaf-mould as they are very tough.
Removal of trees affects bird-life and it was very noticeable that the bird population decreased when several trees near us were cut down. Even non-native trees support masses of wildlife.
Inverglen's idea about offering to share the cost of a professional prune seems sensible and would show your neighbour that you are a being reasonable. It's not cheap - it cost £300 to have ours done.

As said above you can't force your neighbour to cut back or remove their tree and their is no 'right to light' in a garden, or house for that matter. We treat fallen leaves a black gold and make as much leaf mould as we can Bulba even visits the local car park which has several trees and harvests these - helps to make great potting compost!

Moon growe is right - think of that great free leaf mould! Some people go to parks to collect bags of leaves - I saw some today!

Can I pop in with a question here please? I collected the fallen leaves from our Hazel tree last year, bagged it up in an old compost bag, wetted it, stabbed several holes in the bag and stored it in a corner. I excitedly looked into the bag recently to see what leaf mold - if any - I had, and all I seem to have is wet black leaves! Am I doing something wrong? Sycamore leaves were mentioned as being rather tough to make leaf mold - are Hazel leaves tough too?

Hazel leaves can be tough but just how much did you wet them Nariz?

Nariz, I've made leafmould in exactly the way you describe - but I always found it takes 2 years, not one. Have a look at it in 6 months time, and again 6 months later.

Mg, they're VERY wet - soggy would describe it better!
Bamboo - you've given me hope! Perhaps I'm being my usual impatient self! ;o)

Perhaps a little too much wetting?

Going over the leaves with a lawnmower really speeds up making leaf mould. I find Oak, Maple and Beech breaks down quickly and anything with a waxy texture takes an age.

Yes, I've heard of that one, Kildermorie - trouble is .... I don't have grass, so I don't have a lawnmower. I have since moved the bags of last years' black wet leaves into a more airy position and stabbed a few more holes in the bags. Maybe 6 more months will give me some black gold? :o)

We don't either!