Imagine you're facing state surveillance and physical attacks by the Chinese authorities because you're trying to protect Beijing residents from forced evictions. Or you're detained in an immigration removal centre in the UK, with absolutely no idea how long you'll be held there. Or you're facing 15 years in prison simply because of your work defending human rights in Turkey.
You'd probably feel isolated, unprotected, vulnerable.
These are real situations, that real people are going through, right now.
Now imagine you're in one of these difficult positions and you start receiving letters - hundreds and thousands of messages from people all around the world - letting you know that you're not alone and that there are thousands of people that won't tolerate the human rights abuses you're suffering. And that these people will not only stand by you, but will stand up for you.
You're likely to feel comforted, stronger and more determined.
And when thousands of letters start to pile up at the doors of governments or embassies, it's likely they'd have no choice but to take note and respond.
This is the extraordinary power behind Amnesty International's Write for Rights campaign, which every year sees the simple act of letter-writing transform people's lives.
At this time each year, millions of people from all corners of the world write messages of hope and support to individuals suffering human rights violations, and send letters to pressure the authorities to stop the abuses being committed.
And it works. Last year, hundreds of thousands of people wrote to support Chelsea Manning, the US army whistle-blower. She was freed this year after outgoing US President Barack Obama cut short her draconian 35-year sentence. And pro-democracy activist Fred Bauma, who was released from a Congolese prison in August 2016, told us that "letters from Amnesty supporters...were really powerful and helped me to stay strong. They protected us because the authorities knew thousands of people were watching".
It's wonderful to hear the stories of those who've been supported through the letters they've received. Every single year I am amazed by the power that one letter, when multiplied by thousands, can have.
That is why we're encouraging as many people as possible to get involved in this year's campaign. Every single letter written or email sent counts and makes a difference.
And this year we'll be writing for 14 individuals or groups who desperately need this support.
From people held in UK immigration detention centres for an indefinite amount of time and often in terrible conditions, to Shackelia Jackson, a young Jamaican woman whose brother was the victim of an indiscriminate police killing and who is now fighting for justice. From 10 human rights activists currently on trial in Turkey, to Sakris Kupila, a 21-year-old Finnish transgender man who can't be legally recognised as male because he doesn't want to be forced through sterilisation - an absurd requirement of Finland's gender reassignment laws. These are just some of the individuals who'll be receiving thousands of solidarity letters this year.
Five minutes, some pen and paper or an email, is all it takes to show people being denied their human rights that you stand with them. When thousands of individuals speak up together, our voice becomes stronger - and yours can help make it even more powerful.
For more information about the people who we'll be writing for this year and tips on how to write the letters, visit our Write for Rights website. You can also contact your local Amnesty group if you want to find out about letter-writing events happening near you.