There are multiple definitions - click on the translation that matches your context.

Richtlinie

Substantiv

full

guideline

noun

Comparative law notes

This is the best translation when the context indicates that a non-sanctionable framework of action is meant.

Definitions of guideline

(usually plural) official advice about how something should be done or what action should be taken in a particular circumstance

The Government has issued guidelines for the reporting of business expenses.