Marco Silva says this summer's transfer window is "really important" to Everton.
And the Blues boss has revealed he hopes to keep the "skin" of the squad together and then flesh it out with a clutch of signings.
Everton are believed to be looking to add at least six players this summer with the club also ready to offload a significant number of unwanted stars.
The Blues made six senior signings last summer, as well as recruiting young goalkeeper Joao Virginia, and a similar influx of new faces is expected - but Silva says the club must also keep their best players.
"The next market will be really important," Silva said.
"We want to try and keep the best players, to retain the skin of our squad - and add productively.
"This means we have to aim to sign players who will improve our squad.
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"We are happy with the players already here, pleased with their quality and attitude and how they are doing everything we ask of them.
"But we also have a responsibility at a club such as Everton to always be motivated to improve, to want to win every match."
Everton open to goalkeeper reshuffle this summer as Marco Silva says 'decisions to be made'
