Collins says she's got a publisher and plans to wrap up the final chapters over her summer break - in what will likely be a belated Christmas gift to those who closely follow politics.
But while the former lawyer is having a turn at life as an author, she's just wrapped up another project that's taken up years of her time: going back to school.
Collins this semester completed a Graduate Diploma in Occupational Health and Safety, after deciding to jump into the course at Massey University in 2015.
Collins' office wall is adorned with two master's degrees (in taxation and law) from the University of Auckland and a certificate from the Harvard Kennedy School.
Rather, the decision came while sitting in a Select Committee, listening to submissions about health and safety legislation being introduced by her Government after the Pike River disaster.
"What was obvious to me is most of the people who were submitting, and those who were deemed to be expert in the area, were of the left persuasion," the former ACC minister says.
"And I thought: it's better if people on the right know about this, rather than presuming it has to be a lefty that knows anything about it."
Collins had resigned from Cabinet during the fallout of journalist Nicky Hager's book Dirty Politics in 2014, but by the end of the following year had been cleared by an investigation and returned to her Corrections and Police portfolios.
That left her as a Government Minister while also trying to study for two years, and last year doing three papers (nearly a full-time course load) while in Opposition.
"I never give up," Collins says.
"When we were here in Parliament until 10 at night I would often be working on my [studies]."
Collins, 60, admits there were challenges to returning to university after decades away, and to subjects she had not touched since high school.
"When I was sitting down and forcing myself to re-learn maths formulae and chemistry, my brain hurt. I swear I could feel it hurting. But I was not going to give up because I had started it," she says.