This week, Philadelphia officials announced their support for safe injection sites in the city, to be run by private and nonprofit organizations. Because the issue is controversial, we consulted our northern neighbors in Canada who were the first in North America to open these sites, for a sampling of the debate. Read why Toronto City Councillor Giorgio Mammoliti  opposes safe injection sites for another view on this issue

A woman uses the public bathroom of a community centre to inject heroin. She figures it's safer than injecting on the street – it's clean and she won't be robbed. And if she overdoses, she hopes someone will find her soon enough to help her. In cities across North America, this is a daily occurrence.

However, since the summer of 2017, this scenario has changed in Toronto, where the same woman can visit a supervised injection service to inject heroin. She knows that while she's there, she cannot be arrested for possessing or using drugs. She also knows that if she overdoses, someone will administer Naloxone or oxygen and save her life.

North America is in crisis as overdoses in recent years due to opioid drugs, including fentanyl, and related deaths have skyrocketed. In response, Canada has approved over 20 supervised injection services where people can inject drugs such as heroin or cocaine under the supervision of trained health staff and someone will help them if they overdose.  The scientific evidence shows that supervised injection services lead to a reduced number of overdoses, increased referrals to drug treatment, and benefit public order. There are more than 90 facilities operating globally, most within nine European countries and Australia, and many scheduled to open this year in Canada.

Support for supervised injection services continues to increase each year in Toronto. A service that was once regarded as extreme has now been accepted and promoted by public health officials, politicians, community members, and the chief of police. More than 80 percent of Torontonians who participated in recent surveys said they thought supervised injection services would bring benefits to their communities. Attitudes have also changed in Philadelphia with Dr. Thomas Farley, Philadelphia's health commissioner and cochair of the city's opioid task force in favour of opening supervised injection services. Philadelphia's police commissioner is now reported to have an open mind about implementation of this type of service.  These city officials follow others in New York, Boston, Denver, Seattle, and elsewhere across the United States who are advocating for supervised injection services.

You'll probably never notice them and they work best when integrated into existing organizations.

Over 50 places in Toronto and 200 cities in the United States already offer needle- and syringe-distribution programs every day. For over 30 years, these facilities have integrated so well into their neighborhoods that they have gone largely unnoticed — operating quietly but efficiently helps to address the stigma associated with drug use. Adding supervised injection to these programs that operate with a wealth of experience means that they will not significantly change surrounding communities — except by decreasing public drug use, which benefits everyone.

People will use them.

When the first supervised injection service in Canada, Vancouver's Insite, opened, there were wait lines immediately.  In the summer of 2017, community activists erected tents in a downtown Toronto park and opened the first supervised injection service in Toronto. To this day, it relies on volunteer labor and donations to run the "pop-up" service. Since opening, the service was used 4,343 times and of the 151 overdose that have occurred at the site, there have been no deaths. Three new supervised injection services operated by public health and community health organizations have recently opened and early statistics show there is strong demand. A fifth site is planned for Toronto.

Ignoring the problem will make it worse.

Toronto carefully selected the locations of these services to be in communities where rates of injection drug use are high. This is an excellent example of fitting the service to the real, unmet needs of people who use drugs. Without a safe space, we are ignoring a problem that will only get worse — more people will overdose and die and we will fail to prevent infections such as hepatitis C and HIV.

 Supervised injection services are one part of the drug-reduction strategy.

In Toronto and other cities, supervised injection services are just one part of a multipronged approach to reducing drug use that should also include smart law enforcement, prevention, other harm-reduction interventions, and public health programming.

Supervised injection services work.

Research has shown that supervised injection services reduce public drug use and drug-related littering, as well as decreasing the number of overdoses and risky injection practices. They also provide an important way to refer people to drug treatment and health and social services. They are a cost-effective way to improve the health of people who use drugs.

Carol Strike is a professor at the Dalla Lana School of Public Health, University of Toronto. Ahmed Bayoumi is a professor at the University of Toronto and  physician at St. Michael's Hospital.