Stanlake, who has represented his country 26 times, will link up with Dave Houghton’s side between April and September, with the 26-year-old available for all formats, having been a long-term target for the club.
Since making his debut for Queensland in 2015, Stanlake has taken 136 wickets in 113 games across all formats, with his List A and Big Bash performances earning him international recognition.
The fast bowler has seen most of his success come in T20 cricket, where he has taken 81 wickets at an average of 26.53.
That includes best figures of 4-8 for Australia against Pakistan in 2018, while he took 13 wickets for Melbourne Stars during their Big Bash campaign, the second-most for the side.
The tall quick has picked up 21 wickets across eight first class matches, at an average of 31.23, and adds international experience to a promising crop of Derbyshire bowlers.
He’s set to play alongside fellow Australian, Ben McDermott, who has signed for the 2021 Vitality Blast and Royal London Cup.
Head of Cricket, Dave Houghton, said: “Billy is a player we’ve been watching for some time, there’s not too many players of his quality available for all formats, so it’s really pleasing to get him in.
"He’s tall and he bowls at a high pace with a good level of bounce and variation.
“He’s someone who has made his name with the white ball, but he’s determined to show what he can do in first-class cricket as well.
"That hunger will be huge for us, and he’s a great addition bowling attack.”
Stanlake added he was excited to show what he could do in England.
He said: “I can’t wait to get started with Derbyshire and show the supporters what I’m all about, it’s a really exciting time for me.
“I’m keen to develop my red ball game, and this move gives me the opportunity to hopefully help Derbyshire to build on their form across the competitions.
"The club are ambitious, they want to win trophies and hopefully I can be a part of that success.”
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