In recent years 2014 and 2016 have been notable for key moves being made. In the former, Aberdeen added Shay Logan and Adam Rooney, while Celtic signed Leigh Griffiths as well as Stefan Johansen. Two years later, Patrick Roberts headed to Parkhead with Anthony Stokes moving to Hibs. John Souttar and Gary Dicker would join Hearts and Kilmarnock respectively.
In the mid-2000s Rangers made two of their most impressive signings in bringing Barry Ferguson back to the club in 2005 and signing Davie Weir in 2007.
Between then, Hearts famously, or infamously, signed 11 players in the January window as Vladimir Romanov made his mark on the squad which had been challenging Celtic for what was then the SPL title.
This window has already witnessed Ange Postecoglou make a triple swoop from the J-League, while across the city Rangers are on the cusp of breaking their record transfer sale with academy graduate Nathan Patterson who is on the verge of a reported £12million move to Premier League side Everton. A few which could rise further.
On top of that Hibs are very active in the market under new boss Shaun Maloney with Callum Davidson and St Johnstone looking to add heavily with the club bottom of the league. The likes of Hearts, Dundee United and Aberdeen will also likely make key additions.
Scroll down and click through for all the latest news and transfer speculation from around the SPFL an Scottish football.
1. Lafferty a free agent
Former Hearts, Rangers and Kilmarnock striker Kyle Lafferty is available on a free contract after leaving Anorthosis Famagusta. The Northern Irishman scored just once in 11 appearances before agreeing to mutually terminate his contract. (Various) Photo: Craig Foy - SNS Group
2. St Johnstone make Shaw move
Liam Shaw is a key target for St Johnstone this month. The Celtic midfielder joined the club from Sheffield Wednesday and will likely be allowed to leave to gain regular game time. Callum Davidson is keen to add quality to his side as they look to avoid relegation from the top flight. Shaw played often for the Owls before making the switch to Parkhead. (Courier) Photo: Alan Harvey - SNS Group
3. United keeper wanted
Dundee United goalkeeper Trevor Carson is wanted by Morecambe. The Shrimps are managed by Stephen Robinson who was Carson’s boss at Motherwell. Any deal, however, would have to suit the Tannadice side with the goalkeeper under contract until the end of the season which could mean signing a replacement. (Courier) Photo: SNS Group Craig Foy
4. Killie to appoint McInnes
Kilmarnock are closing in on the appointment of former Aberdeen boss Derek McInnes. The Championship side have been on the search for a new manager following the sacking of Tommy Wright last month. McInnes, who has been out of work since leaving the Dons towards the end of last season, has been in talks with Killie in what would be quite the coup for the Rugby Park side. (Various) Photo: Craig Williamson - SNS Group