Actress and activist Emma Watson is urging fans to make a "one-degree shift" to contribute to the "global wellbeing" after guest editing a special edition of Vogue Australia.

The Harry Potter star also serves as the cover girl for next month's (Mar18) edition of the top magazine, which focuses on sustainability and those working to make a positive change in the world.

Emma has taken to Twitter to show off her two different covers, thanking Vogue Australia's editor-in-chief, Edwina McCann, for giving her the opportunity to try and inspire change.

"I helped guest edit @vogueaustralia's March issue dedicated to conversations about sustainability and 'Designing the Future'," she captions the images.

"I am so proud of this! @Edwinamccann thank you for making my editing dreams come true."

The Brit has also shared a link to her guest editor's letter, in which she highlights ways in which the world is changing for the better, appearing to reference the current Time's Up movement to end sexual misconduct, discrimination, and inequality in the workplace.

"After a year dominated by an alarming newsfeed, it seems we have hit a turning point in 2018," Emma begins. "Silenced voices are becoming amplified and media outlets are shining a spotlight on the people and groups challenging for change. The pages to follow in this issue, Designing the Future, is a part of that change."

"The word 'change' can be intimidating, riddled with expectation of outcomes and fear of failure," she continues. "So I want to propose something to you: when steering a boat, a captain can shift the wheel one degree and it drastically changes the course of the boat."

Encouraging readers to apply the practice to their own lives for a better future, she shares, "I would like to challenge you, after reading this issue, to make a one-degree shift, because a small change can make a huge difference."

After thanking publication bosses "for allowing me this platform to share stories and movements I care about," Emma signs off with a call to action.

"Lastly, thank you to anyone picking up this issue and reading it," she concludes. "You are the biggest piece to the puzzle of our global wellbeing. Join me in a one-degree shift!"

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