A medical cannabis dispensary is a place where one can purchase weed legally. Majority of the states have legalized marijuana for medicinal use, yet, there are some that haven't. In such states, dispensaries do not exist legally; therefore, purchasing or obtaining weed becomes more of a hassle; you have to resort to other means like buying from someone who has it or growing your own if you can.

As of now, there are 29 states in the U.S where weed is legalized for medical use and these dispensaries (in those states) function as centers for proper distribution of medical cannabis to patients who need it. They are mainly regulated by state laws and authorities; they provide information on dosages, different strains, forms in which it can be taken etc.