Broom will qualify as a local player in England.
He holds a United Kingdom passport as his father, Dick, was born in Norwich. By doing that, he has given up any chance of playing for New Zealand again.
Broom will join Otago team mate Hamish Rutherford at the county, which is in the second division of the English County Championship, and lies in the bottom reaches of the table.
Broom, who has rejoined Otago this season after a season with Canterbury, said yesterday the offer was too good to not take up.
''After I had made the decision to move back south I looked into the chance of going and playing county cricket,'' he said.
''The time was right and I got Ruds [Rutherford] to do a bit of digging for me.''
Broom said once Derbyshire came up with the offer it was not a hard decision to accept the opportunity.
''I had looked into it a few years ago but had turned it down. I'm 31 now, nearly 32, and thought if I don't do it now then I'll never do it.''
He was realistic about his chances of getting to play for New Zealand again, with plenty of candidates looking to force their way into the New Zealand batting line up.
Broom made his international debut in 2009 and has featured in 22 one day internationals and 10 twenty/20 internationals for New Zealand.
The right handed batsman has also played in 109 first class games, scoring 6427 runs at an average of 40 and hitting 15 centuries, with a top score of 203 not out.
He played three seasons for Canterbury and then moved to Otago for nine seasons before moving back to Canterbury last season.
Broom, rather unluckily, has not played test cricket for New Zealand.
He will play as a local player for Otago this coming summer but, in subsequent years, will qualify as an overseas player for the Volts.
''It is an exciting opportunity, but first of all I want to have a good summer for Otago and then come back and play for Otago for the next three or four summers.''
Broom said he did not know a lot about the Derbyshire team, although it was said to be a young side which needed some experience, which he hoped to provide.
Broom has relatives on his father's side still living in the United Kingdom.
He and wife Melissa will take their family, sons Connor (4) and Luie (2), to the United Kingdom next year.
