Northwood has been appointed executive director of the ACA following the departure of chief executive Ken Bishop. She will continue as Two Sides Australia national manager, a position she assumed last May.
Northwood told ProPrint that working across two associations would allow her to better promote print's environmental credentials.
"Our industry really needs to unite a lot more and get a common message out so we can challenge some of those myths out there," she said.
[Opinion: It's time to choose sides]
"The ACA and Two Sides have common objectives… and this allows us to have that stronger united voice, so I can go and do one presentation and talk about the industry at large, rather than about one particular component."
The two associations also have board members in common, she added.
Northwood told ProPrint she would remain at Geon, which she joined in 2009, "but in a much more limited role".
"I'll continue to work with Geon on various projects that I'm already helping them with. It will be more on a project basis than on how-many-days-per-week basis," she said.
"I've been with Geon a long time and have a lot of loyalty and time for [chief executive] Graham Morgan. I've worked closely with him and will continue to do that."
[Related: More news about Two Sides Australia]
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