Here's a start:

1. Legalise all drugs
2. Allow people to make/grow their own if they want.
3. Classify drugs between those requiring medical/pharmaceutical prescription and lighter drugs that can be sold more openly (such as marijuana and alcohol)
4. Only allow persons of 18 years and older or another legally determined age to legally purchase drugs. Harder drugs would be sold by Pharmacies/Chemists, and only after a consultation to ensure users are aware of risks and to determine safe dosages. Marijuana could be sold from liquor stores/offlicences as alcohol is now
5. Enforce quality standards on all drugs
6. Treat Addiction as an illness, and provide medical services to help addicts beat their problem.
7. Tax drugs and use the income to fund drug use training in schools, quality enforcement, addiction assistance/medical help for addicts, and medical/pharmaceutical training
8. Make it illegal for anyone to supply drugs to minors, with harsh penalties (say 1 years mandatory community service followed by 10 years in prison)
9. Impose harsh penalties (large fines, community service and imprisonment) on anyone who causes harm to anyone else whilst under the influence of drugs. No distinction is made between alcohol and other drugs. Driving whilst under the influence of drugs and alcohol should be treated as a major offence, whether someone is injured or not. It is effectively attempted manslaughter, at the very minimum. Big fines along with compulsory re-education and community service (a substantial amount of it-like 2 years) should be followed by a mandatory minimum jail term for any subsequent offence.
10. Make the giving of drugs to another person without their consent a serious criminal assault, punishable by a combination of prison and mandatory community service.

By legalising drugs and items 1-10 above, we would be doing the following:

1. People wishing to use drugs could do so without being a criminal
2. Children would not come into contact with the criminal underworld like they do now. Life would revert to a situation where most people would have nothing at all to do with crime.
3. Drug deaths and medical costs would decline radically because drugs would be quality controlled, and not mixed with harmful substances which cause most of the medical problems. Overdoses would be very rare, as users would know their correct doses.
4. All the money made by drug traffickers would stay in the mainstream of society, and not go to funding other criminal activities.
5. Street crime would virtually disappear, along with its main cause, getting money so an addict can fund their next fix.
6. The growing division in our society between the police and people generally would reverse, as so-called 'victimless crimes' would no longer be illegal.
7. Instead of £$Billions each year going to criminals, governments could collect taxes on drugs sold legitimately through off-licenses, drug stores, pharmacies and liquor stores. You can bet the government would like this! Wake up you politicians out there!
8. A new respect for individual rights would invigorate our society
9. Driving under the influence of any drug would be seen as a serious crime, requiring recompense to the community, even if no one had been hurt.
10. The fascination of drugs to children, part of which is driven by its present illegality and anti-establishmentary disposition, would reduce dramatically. Drugs could be openly discussed, and whilst experimentation would never stop (as it never has with tobacco or alcohol), the interest in the harder drugs in particular would decline, as their 'on the street' illegal connection through drug dealers would cease.
11. Our streets would be safe again, with no need for gang wars over drug territories, etc.