ALEX Salmond's decision to step down as First Minister came as a surprise on Friday.

But the manner of it was typical of the man.

As I would have expected, he made the announcement entirely on his own terms, in his own time and with all of his trademark style and panache.

He has a huge amount to be proud of. His achievements as SNP leader and Scotland's First Minister are second to none.

He led the SNP from being a minority party into one of government - first as a minority and then, against all the odds, as a majority - and he has undoubtedly given our country a renewed self-confidence.

Through policies such as the council tax freeze, free prescriptions and the scrapping of tuition fees, he has made life better for hundreds of thousands of Scots.

It was his record of competence and delivery that led to his stunning re-election in 2011.

And last week, he inspired 1.6 million of our fellow citizens- including a majority in this city of Glasgow - to vote Yes to independence.

I owe Alex an enormous personal debt of gratitude.

I first met him when I was only 18 years old.

He encouraged me to become a parliamentary candidate in the1992 General Election when I was just 21.

In other words, he believed in me long before I believed in myself. He has been my friend, mentor and colleague for more than 20 years.

Quite simply, I would not have been able to do what I have in politics without his constant advice, guidance and support over all of these years.

Over these past 10 years, it has been a privilege to serve as his deputy. I am clearly biased, but I think we have made a great team.

Alex has been a great boss - he has always trusted and encouraged me to find my own way, but has been there to support me whenever I have needed it.

Alex's announcement last week raises the question of whether I will be a candidate to succeed him as SNP leader.

The fact is that whoever the SNP chooses to be its new leader will have the biggest of boots to fill.

Personally, I can think of no greater privilege than to lead the party I joined when I was just 16.

However, it is a big decision and one I am considering carefully.

My priority over the last few days - after the rigours of a long, hard referendum campaign, has been to get some rest and spend time with my much neglected family.

I have also wanted the focus to be entirely on the outstanding record and achievements of the finest First Minister Scotland has had.

Alex Salmond is one in a million and although his tenure as FM is coming to an end, I have no doubt that he will continue to make a big impact on Scotland for many years to come.

Scotland has much to thank him for and so do I. So, thank you, boss - for everything.