I WILL be the Member of Parliament for Ochil and South Perthshire only until the next election. After that, OSP – as it's affectionately known – will be no more.

This is the result of Boundary Commission changes which see the constituency change name and shape along with many other seats across the United Kingdom.

So, what's it all about? Every few years the Boundary Commission – a statutory body – sets out to assess parliamentary constituencies.

In theory, they should all have roughly the same number of constituents with only two exceptions – Na h-Eileanan an Iar (the Outer Hebrides) and Orkney and Shetland.

The last time the commission made changes was in 2005 when Ochil and South Perthshire was created.

The commission always asks for submissions as part of their deliberations. But those with long memories tell me these have limited effect.

I lobbied for the names Clackmannanshire and Kinross-shire to return. After all, these ancient counties were represented in the pre-Union Scottish Parliament.

Post-Union they were paired as alternating constituencies at Westminster. One General Election Clackmannanshire would have an MP. The next election it would be Kinross-shire. History and community matters.

It's clearly a good idea for seats to have manageable numbers of constituents. So at first glance it's not hard to see why the commission tries to maintain roughly equal numbers.

But here's a problem. Densely populated cities have tens of thousands of people living in a small geographical area.

But what of the Highland and Islands? Ross, Skye and Lochaber is bigger than Luxembourg. Argyll and Bute has 23 inhabited islands.

Both have only one MP who must work in London all week. So accessing the more remote parts of these constituencies presents a challenge very different to any faced by central London MPs, who are only a short cycle ride away from the outer reaches of her or his seat.

And as if that didn't create enough of a problem, the Commission has decided to reduce the number of Highland seats next time round.

Overall, Scotland will have its representation cut from 59 to 57 whilst England's will increase to 543. Scottish MPs can always be outvoted on any matter at Westminster.

On a personal basis, I'll be very sad to bid a fond farewell to my constituents in Perthshire and Kinross-shire.

My team and I have handled thousands of cases from both counties since the last election. I've made many friends there and have been very touched by all the lovely messages sent by constituents and businesses I will lose.

The largest part of my existing constituency transfers to the newly created Alloa and Grangemouth seat. I'm looking forward to making new friends and seeking out fresh challenges in Grangemouth and parts of Falkirk now joining Clackmannanshire.

Being an MP is a challenging and fascinating job. But there's no more satisfying part of the role than constituency work.

MPs are often the last port of call for folk who need help. Trying to help is a uniquely rewarding part of the job.