In Marrakech there are two types of taxis, there are the small yellow ones which are called “Petit Taxi” (French language is very much apart of the Moroccan culture) and the larger taxis (old Mercedes from 80s) which are called “Grand Taxi”.
 
The “Petit Taxi” have meters but the drivers tend to forget using them with tourists and it is always good to negotiate the price in advance, but keep in mind that at night the prices are 50% more than during the day (this rule applies even to locals). The maximum number of passengers this taxis can hold is 3. You can catch them in the streets or in the small taxi station. You can also catch them in front of hotels but the taxis that are standing in front of the hotels cost more because sometimes they spend a long time waiting for customers. A ride from the famous Jamae El Fna Square to the Gueliz in the new town should not cost you more than two euros.
 
The “Grand Taxis” do not have meters and are allowed to carry more than 4 passengers. You can find them normally in front of hotels or you can ask the concierge at your hotel to call you one. They are of course more expensive than the small taxis and the price should be negotiated in advance.
 
One little tip when crossing the streets in Morocco: do not expect cars to stop for you when you are crossing the street (even when you are using a zebra crossing)!

With the arrival of the "low fare" airlines into Marrakech, the number of independent travellers has been boosted substantially, and the taxi drivers are taking advantage of their innocence.  Here are two simple guidelines:

1. No Marrakchi would pay more than 10 Dirhams for a ride across the city in daylight, possibly rising to 15 Dirhams at night.  Carry small denomination notes or coins, pay what you think is fair. Leave the money and walk away if the driver argues: he won't abandon his car to follow you.

2. Rates for taxis from the airport into town are posted on signage in the airport car park.  They are kept up to date, and this is the maximum price you should pay.  If your driver asks for more, walk into your hotel reception and ask them to intervene.