"There will be no more floor-crossings," Smith told reporters Wednesday.
She also said she is not resigning as leader and that the Opposition Wildrose is ready to start anew doing what it does best — holding the Progressive Conservative government's feet to the fire.
"After a couple of days' reflection with my caucus, we are, as you can see, back at it, doing our job holding the government to account," Smith said.
She said she has taken stock with Albertans and with political confidantes in the last few days after two members of her caucus quit to join the governing PCs.
"They recognize that the only reason why the government is making some steps in the right direction is because they're being pushed in that direction by us," said Smith.
"We've been an incredibly effective Opposition. I'm now on my fourth premier. And we believe that there's still a lot of work to do to hold them to account."
Wednesday was the first day Smith took questions from reporters after her seniors critic, Kerry Towle, and agriculture critic Ian Donovan crossed over to the PCs.
Both said problems within the Wildrose party and the promise of reform under Premier Jim Prentice lured them across the aisle.
Towle was a bitter blow.
She had been the Wildrose's dogged and high-profile fighter to fix problems in seniors care and was considered a rising star. She has promised, as a government backbencher, to continue her fight for the disadvantaged.
Smith said that may not be as easy as Towle thinks.
"I think it's a shame that one of the most outspoken advocates for our most vulnerable has now been silenced by sitting on the backbenches in the PC caucus," she said.
"That's what happens in the PC caucus. It's whipped votes and people don't have the ability to stand up and represent their constituents the way we do."
She said it was a personal blow, as well.
"We were friends, and I say that in the past tense," said Smith.
What is Towle to you now? she was asked.
"She's a member of the party across the aisle."
Emotions ran high after the defections. On Tuesday, someone in the Wildrose office sent a picture to Towle of her coffee mug smashed to pieces.
"I don't know how (the cup) got smashed, but I know it was incredibly inappropriate to send her the picture. I understand that the staff member feels very regretful," said Smith.
"My chief of staff talked to him and let him know it was completely unacceptable."
NDP finance critic Brian Mason, a former party leader and longtime legislature member, said Tuesday that Towle's decision was a breathtaking defection for someone so close to a leader.
"It was the greatest act of personal betrayal that I have seen in my 25 years of elected office," said Mason.
Smith is trying to pull her caucus and party out of a tailspin following four byelection defeats to Prentice on Oct. 27.
The defeats led to internal criticism of Smith: that the byelection strategy was too negative, that she had lost touch with her party and caucus.
Smith agreed the byelections were a turning point. She has a new chief of staff and said she is looking for a new executive director and campaign team.
"There will be a lot of changes that we'll be making over the course of the next weeks and months. That, I think, is going to be really healthy for the party."