If you haven't heard yet, today - May 17 - is the International Day Against Homophobia, Biphobia and Transphobia. Otherwise known as #IDAHOBIT, it's a worldwide celebration of gender and sexual diversities that's expected to be marked in around 130 countries. Literally thousands of events are scheduled to take place - from queer cycle parades in Albania, to rainbow flashmobs in Russia, to same-sex wedding ceremonies in China.
In around 35 countries where same-sex relationships are a crime, activists are expected to take action anyway, regardless of laws.
For a taster of the scale, diversity and bravery of actions expected today, you can watch this new video - produced by the awesome campaign 'Free and Equal', run by the United Nations. If you're anything like me, you'll need some tissues at the ready.
What's the global situation for LGBT people?
Over the past quarter of a century, great progress has been made on LGBT rights worldwide. 40 countries have decriminalised homosexuality and over 30 have outlawed homophobic hate crimes. Over 60 countries now legally protect LGBT people at work and 15 recognise same-sex marriages.
But huge challenges remain. Sex with someone of the same sex is illegal in 75 countries, and it's punishable by death in 10. That means 40% of the world's population live in countries where LGBT people can be imprisoned, just for being themselves. Over 400million people live under laws which punish same-sex relationships with the death penalty.
For trans people the legal situation is, in most cases, even worse. Most governments deny trans people the right to legally change their gender on official documents (just 50 countries allow this).
Violence is a particularly big problem for trans communities. Shocking figures released by Transgender Europe show that, in the first 70 days of 2016, a trans person was killed in a lethal transphobic hate crime every 24 hours - and this is in the Americas alone.
What's the focus this year?
This year's theme for the day is mental health and well-being. One of the reasons it was chosen by activists is to challenge the idea that being LGBT - just being ourselves - is something that needs to be 'cured'. Horrific conversion clinics are one of the clearest manifestations of this idea. So too are unhealthy attitudes, including here in the UK. At Stonewall, our research has shown that one in 10 frontline healthcare staff has witnessed colleagues expressing belief that someone can be 'cured' of being LGBT - a shocking figure we're working to reduce.
But mental health and well-being questions go far beyond this too.
In all but seven countries in the world, trans people have to get doctors to classify them under a specific mental health classification, in order to legally change their gender on official documents.
In practice, this means that to get something as simple as a passport, identity card, or healthcare file with their correct gender identity listed on it - and therefore to avoid discriminatory situations, or to get access to vital healthcare - the vast majority of trans people have to go through medical gatekeepers.
This includes in the UK. At Stonewall, one of our biggest upcoming battlegrounds is reforming the UK's outdated equality laws, so that trans communities don't have to go through unnecessary and bureaucratic hurdles, just to get their identities recognised.
And just as LGBT people are often stigmatised within healthcare settings, so too are they often isolated from adequate care for their mental health and well-being.
We know that LGBT people experience mental health issues like anxiety and depression in greater numbers than non-LGBT people.
LGBT young people who are bullied, or isolated from adults they feel they can talk to about their mental health and well-being, are more likely to experience depression.
So research also clearly shows the importance of allies - of people who can listen to, stand by the side of, and stick up for LGBT people who are experiencing mental health difficulties.
And that's also one of the things that makes IDAHOBIT so fantastic: the range of allies who take action in support of LGBT activists worldwide. Whether it's LGBT people in the UK standing by the side of LGBT activists overseas, or non-LGBT people standing up for LGBT equality, it's truly a day for everyone to take action and show one another we are #ByYourSide.
How can I get involved?
You can join the action on social media - via the main hashtags for the day (we'll be signal boosting some our favourite actions too), #IDAHOBIT and #IDAHOT.