Netherlands bowler Paul van Meekeren has been rewarded with a two-year deal at Somerset following an initial three-month contract with the county.
The 23-year-old, who mostly played for the second XI in 2016, featured in two first-team T20 Blast matches.
The seamer has played in 15 T20 internationals and two one-day games for the Netherlands.
"He's shown he offers something a bit different," director of cricket Matt Maynard told Somerset's website.
"We look forward to having him here with us for at least the next two seasons."