Many visitors to Venice are not be aware of the by-water options available for transportation from the Marco Polo Airport to the Islands of Venice.
Alilaguna is one such option. They operate large, covered boats with room for luggage storage. . Here’s a link to their route maps (http://www.alilaguna.it/en/lines/lines-map). Information on fares is here: http://www.alilaguna.it/en/tickets1/fares.
They provide a good option for transportation from hotels in the eastern part (around St. Marks, for instance) of the city to the Cruise Terminal (labeled Terminal Crocere in in the center-left area of the route map), especially via the “blue line.”
They also provide a decent option for transportation from the airport to/from the island (whether to hotels or the cruise terminal). The downside to this option is that there is a decent hike from the airport exit to the docks (about 900 feet/275 meters) where you board the Alilaguna (and water taxis). Also, these boats are too large to traverse the interior canals of the islands so, if your hotel is somewhat inland, you’ll have to schlep your luggage over a couple or a few staircase bridges on your way there.
Note that the Alilaguna is a separate service from the “Vaporetto,” which operate more like “public water buses,” are sometimes crowded and are more appropriate for transport during your stay there.
Also, Water taxis, are a decent option and are generally the fastest way to get from point a to point b. As always, advise your clients to be clear on the fare before boarding. Note that many hotels in the main part of the city have dock entrances from their rear where your clients can be delivered directly from a taxi into their hotel where a bellman is ready to help with luggage. There’s really no more convenient or impressive way to start your stay in Venice. As usual you clients will have to pay a premium for this convenience, but the fares are not really “outrageous,” especially for folks who’ve just arrived after a long flight from the US. And, if your party is large, a taxi can compete in price with the per person rates of the Alilaguna.