She will get two chances to drive the FW36 in the Friday morning practice sessions at grands prix, at Silverstone and Hockenheim in July.
"Competing in a formula one race has always been the ambition," she told the Telegraph, "and as of last week I'm one big step closer.
"I just need the chance. And I'll do everything I can to make it happen."
In the male-dominated world of motor racing, Wolff has struggled at times to be taken seriously.
Some think her burgeoning role at Williams smacks of little more than marketing.
"There are far more deserving cases, male and female, who would merit the chance to drive in an F1 practice session," Simon Arron, editor at Motor Sport magazine, is quoted by London's Times newspaper.
"Whether this is tied into any marketing programme, I don't know, but she doesn't have a record which suggests she should be near F1."
Former F1 race winner David Coulthard, however, said Wolff is definitely a top-level driver, having been beaten by her "more than once" in the German touring car series DTM.
"Does she have that last bit of speed to make it as an F1 driver? I absolutely don't know," said Coulthard, a fellow Scot.
"She will have her opportunity and if she delivers, she will continue. If she doesn't she won't -- and we'll all have the answer."
For how long Wolff will continue her racing career, however, is not clear.
She admits that when the urge to become a mother overtakes her need for speed, she will quit.
"I will never race again once that (starting a family) happens," said Wolff.
"I want to have kids and I know that when I do have them I have to have finished with this. Because I could never put myself at risk knowing that there is a child at home relying on me.
"At the moment I love my life but I think that there will come a point where the need for a child will be greater than my need to race, so I'm just waiting for that moment," she admitted.
Meanwhile, the correspondent for the Finnish newspaper Turun Sanomat, Heikki Kulta, says he is in London for the launch on Thursday of the new Martini-branded livery of Williams' 2014 car.