[dr_dshiv]

Having safe, stable shelter would seem to be a prerequisite to helping people deal with drug addiction and mental illness.

Baxter, A. J., Tweed, E. J., Katikireddi, S. V., & Thomson, H. (2019). Effects of Housing First approaches on health and well-being of adults who are homeless or at risk of homelessness: systematic review and meta-analysis of randomised controlled trials. J Epidemiol Community Health, 73(5), 379-387.

[Viliam1234]

We should build enough shelters for homeless, but separately for those who are addicted and those who are not. (Maybe more than two types of shelters.)

For a homeless person who is not addicted, sharing the shelter with the addicted ones means constant worry that even the little stuff they own gets stolen the moment they stop paying attention, and also lack of sleep because of the constant screaming and fighting during the night.

[bluGill]

That is one factor, but it isn't everything, there are still other factors so don't overstate it

[ModernMech]

As someone with experience with severe mental illness (BP1) I don’t think it’s possible to overstate the importance of a stable environment when dealing with an acute mental health crisis.

[cagenut]

downvoted because they clearly said 'pre-requisite' which is in no way an overstatement.