Possessing a passport in the course of validity is mandatory. The necessity of a visa depends on your nationality. Embassies and consulates will be able to orient you before and during your trip.
Papers
To avoid any inconvenience upon your arrival in Morocco, check well that you have in your possession a passport in the course of validity.
Visa
No visa will be requested from nationals of the European Union as well as those of Switzerland and Canada. For all nationalities, the maximum duration of the tourist trip is 90 days.
Embassies and consulates
While preparing your departure, note the contact details of your embassy and the consulates installed in the region. You will be able to renew your papers there in case of loss and obtain all sorts of advice (health, safety, etc.). Generally, each diplomatic antenna has an emergency number to be used only in case of necessity. A social service is most of the time capable of helping you, even in case of emergency.

To remember
Check the validity of your passport and inform yourself about your diplomatic representations.