A new study by drug taskforces around the country, shows that three quarters of people who've been intimidated by gangs or drug dealers don't report it to Gardai.
The research comes as a conference on drug policies takes place in Dublin later.
President Michael D Higgins and the Drugs Minister Aodhan O Riordain are among the speakers at today's event as part of Citywide's Drugs Crisis Campaign.
The decriminalisation of drug users will also be discussed.
Co-ordinator of Citywide Anna Quigley, says drug addicts and their families are vulnerable to intimidation from dealers and gangs.
