Pompey so far have brought in two players – Sean Raggett and Cameron Pring - ahead of a renewed promotion push.
Meanwhile, the likes of Peterborough, Sunderland, Charlton and Hull have also been improving their sides as they push for the Championship.
But what about the players that clubs have lost? The departures of key men can often prove detrimental to teams' ambitions.
Scroll down and click through the pages to see who each side will miss...
Meanwhile, the likes of Peterborough, Sunderland, Charlton and Hull have also been improving their sides as they push for the Championship.