The Princess of Wales has called for an end to the "stigma" surrounding addiction, and urged people to offer "empathy and support" to those dependent on alcohol, drugs or gambling.
Catherine, who sent the message to mark Addiction Awareness Week, said "significant progress" has been made to better understand addiction, but warned more needs to be done.
The princess is the patron of The Forward Trust, a charity that tries to break the cycle of addiction and is behind the campaign running from 23-30 November.
Catherine, who has also campaigned on mental health issues, draws parallels between the two conditions in her message.
She said addiction was "not a choice or a personal failing, but a complex mental health condition that should be met with empathy and support".
She added: "But still, even now in 2025, people's experience of addiction is shaped by fear, shame and judgement. This needs to change.
"The stigma surrounding those who face addiction allows it to thrive behind closed doors, impacting families and communities, and ultimately ruining lives."
The princess said that many people will know someone who is struggling with addiction.
"Now is the moment to show our compassion and love to help them, or their friends and family, to reach out to organisations like The Forward Trust for support," she said.
"Recovery is hard, but with the right treatment it is possible. And this begins with a conversation, a listening ear and showing we care."
Catherine launched the first Addiction Awareness Week in 2021 on behalf of the trust and its Taking Action on Addiction campaign.
She concluded her message by urging people to have open conversations to bring addiction and the harm it causes "out of the shadows".

Catherine launched the charity's campaign in 2021
It is not the first time Catherine has spoken out on the issue of addiction.
In 2022, she gave her personal support to people struggling with addictions, telling them shame should not stop them getting help and urging a more compassionate public attitude towards the condition.
Former England and Arsenal captain Tony Adams, who spent 11 years in addiction, has also recorded a video to launch a series of films demonstrating the power of open conversations in the journey to recovery.
In the film, he reveals that a conversation with his mother-in-law Barbara was the catalyst to getting help.
Adams, who is now chairman of trustees at the Forward Trust, said: "If you are struggling with an addiction or a mental health issue, then please reach out and get the appropriate help. The greatest thing I ever did was to say, 'I can't do this'."
The charity provides services including helping with employment and addressing the problems of addicts and addictions in prison.
Before the Princess of Wales became the Forward Trust's patron, she had twice visited the charity's substance misuse services at HMP Send, a women's prison in Surrey.
The trust has also called for greater recognition of the scale of gambling inside prisons.

Steve Jones: "The Princess of Wales discussing these issues will help remove stigma - anything to help people understand and have empathy when they see or hear about addicts is a good thing"
Several people who have struggled with addiction contacted the BBC after reading Catherine's message.
Steve Jones said he "turned to drink and drugs" to "help blank it all out" after spending 40 years in the military. After losing friends in a helicopter crash and witnessing a man die in a car accident, Mr Jones said he "had bottled up all these emotions which all came out five years ago".
He believes the Princess of Wales' open discussion of addiction and mental health will help to remove the stigma and encourage understanding.
Another reader, who only wanted to be named as MD, said they had been struggling with gambling for about 20 years, calling it "an addiction that you can only hide by lying and deceiving people".
MD feels that Addiction Awareness Week and Catherine's message has "amazing intent", but "the stigma and shame on something like this literally drives people to suicide."
Additional reporting by Alex Emery