He told the Otago Daily Times yesterday he relished the opportunity of juggling three complex portfolios.
He had asked to keep Immigration, because of important work under way in the portfolio.
Immigration was also a good fit with the labour role, which has been renamed workplace relations and safety.
''A lot of the immigration stuff is on jobs, and the way foreign migrant workers are being treated.''
In the labour role, Mr Woodhouse will be responsible for controversial employment amendment legislation that was shelved before the election when the Government lost its majority after Act New Zealand MP John Banks was found guilty of filing a false electoral return.
Mr Woodhouse would not rule out making changes to the legislation, although he supported its general direction.
He wanted to talk to officials, and get to know the proposed legislation in detail, before making any decisions.
Unions have said it will weaken bargaining rights by allowing employers to walk away from pay talks.
He expects it to be controversial.
''Historically, any attempt by a National-led government to amend employment legislation always carries with it some form of resistance, and I don't think that's going to change anytime soon.''
The law governing tea breaks - the most publicised aspect of the proposed amendments - was far too inflexible and should change, he said.
He said the police role was probably the least challenging of the three - although he was not complacent about it.
An area he has targeted for improvement is crime resolution rates, he said.
The last two police ministers had done a good job in the portfolio, he said.
Asked if he wanted the health portfolio, which has been assigned to Dr Jonathan Coleman, he admitted he would have been ''delighted'' but was not upset about it.
Mr Woodhouse looked forward to working with Dr Coleman on Southern District Health Board's financial issues, which must be resolved before it can afford a Dunedin Hospital rebuild.
Mr Woodhouse considered it unlikely the Cabinet would consider a business case for a new Dunedin Hospital this year, although he was open to being surprised.
Earlier this year, then Health Minister Tony Ryall said he expected the Cabinet to consider a business case next year.
However, Mr Woodhouse said the timeframe was too tight, as a hospital had to be carefully planned to cater for the area's health needs over the next one or two generations.
He said he had been upfront on the campaign trail about the timeframe.
Ranked 17th in the new line-up, Mr Woodhouse was promoted to Cabinet in January this year after a fast move through National's ranks. Before this year, he was a minister outside Cabinet, and has served as chief whip.
