The Scottish government is holding a drugs summit in Glasgow just 24 hours before the UK government hosts its own event in the same venue.
Both aim to find solutions to the public health emergency that has seen drug misuse deaths reach record levels.
Figures show there were 1,187 drug deaths in 2018 and the numbers for last year could be even higher.
The Scottish government said the summit would hear from people with “lived experience” of drug use.
About 350 delegates will attend the event at the Scottish Events Campus (SEC).
It has been arranged alongside Glasgow City Council whose leader said she hoped agreement could be reached over the two summits to allow the city to pilot drug consumption rooms.
It is more than three years since the council first proposed allowing users to take their own drugs under the supervision of medical staff at a special facility in the city.
They hoped it would encourage users who inject heroin or cocaine on the city’s streets to enter a safe and clean environment.
The so-called “fix rooms”, which would be the first of their kind in the UK, have the support of the Scottish government but drug laws are reserved to Westminster.
The UK government’s Home Office has refused to allow the Glasgow plans, saying a range of offences would be committed, including possession and supply of controlled drugs and knowingly permitting the supply of a controlled drug on a premises.
The UK government confirmed last month it would be holding a summit at the Scottish Events Campus on 27 February aimed at tackling problem drug use, chaired by Home Affairs minister Kit Malthouse.
At the event, Prof Dame Carol Black, the woman tasked with carrying out an independent review of drugs policy, will present her findings.
The latest figures for drug misuse deaths in England and Wales showed a large rise but the rate was four times higher in Scotland.
Last summer, a report by the European Monitoring Centre for Drugs and Drug Addiction highlighted Scotland as a “point of concern” because it had the highest overdose mortality rates in Europe.
Scotland’s Public Health Minister Joe FitzPatrick said his summit would make valuable contributions which would help inform the Scottish input to the UK Drugs Summit on Thursday.
The Scottish summit will also have training in the use of Naloxone which reverses the effect of an opioid overdose.
‘We were denied the chance to save our son’
By BBC Scotland social affairs correspondent Chris Clements
Dundee is repairing “fractured” services after a damning report found they had failed a generation of addicts in the city.
Immediate plans include better connections between services and charities helping users, as well as same day prescribing and following-up with those who suffered non-fatal overdoses within 72 hours.
However, one family feel the plans came too late for their son.
The parents of Garry Donnan criticised police for failing to disclose a previous overdose the day before their son died.
The 29-year-old was found unresponsive in the second floor bin area of Elders Court tower in Dundee’s Lochee area on Thursday 12 September.
It is understood he was revived by medics using Naloxone, which temporarily reverses the effects of opioid overdoses.
After refusing to attend hospital, police officers spoke with his partner and parents – but told them he had suffered a head injury rather than an overdose.
Garry returned to Elders Court the next day to buy drugs. He died in the first floor bin area of the tower and lay undiscovered for two days.
His father, Garry Snr, told BBC Scotland’s The Nine: “Because they told me it was a fall, I believed them because it was the police.
“I still think I was denied the chance the chance to save my son, because I’d have went and got him and taken him away from Dundee for a few days.”
Mr Donnan added: “I still say to this day that if the police had been honest or said, ‘I’m sorry, we can’t tell you’, I would’ve guessed what it was.”
In a response to the family, police state: “Your son agreed for his partner to be contacted but refused to provide consent for police to relay that the circumstances were drug-related, that police only inform her that he fell and bumped his head.”
Chief Inspector David McIntosh said officers had treated Garry “with fairness and compassion, but were legally-bound to respect his decision not to disclose this information”.
He added: “I do agree that a better course of action may have been to inform the family that Garry had not consented to us telling them the full circumstances.”