Hawaii Inter-Island Flights
Traveling on and between the Hawaiian islands is much easier than getting around most visitor destinations. There are no trains, very few taxi companies (unless you are in Honolulu or the bigger towns like Lahaina), and there is little land to get lost on leaving ample room for backtracking.
Hence, you really are allowed to practice your navigational, awareness and planning skills with a rental car on most islands.
First off, the only way to get from island to island is by air, unless using the Ferry from Maui to Lanai. There will be a new Super Ferry launched in July of 2007 that will service Oahu, Maui and Kauai. Until then, if you want to travel between any of the four major islands, you must do it by air.
Luckily, because of additional small airlines recently introduced, airfare is much cheaper than it was a year or so ago. If booked a week or two in advance, one way tickets can be $29 or lower.
The inter-island jet services are Hawaiian Airlines and Aloha Airlines which service all off the islands. Go! Airlines flies to the four major islands as well and their flights are inexpensive. They are a favorite among locals because of their availability and pricing.
There are also inter-island services with propeller aircrafts such as Island Air, Mokulele Airlines and Pacific Wings. These are small planes that sometimes fly out of smaller airports. The bonus is no lines, and the challenge is that they can be a bumpy ride and sometimes fill up fast.
Flying to Hawaii from somewhere else you will most likely use one of the airlines such as Hawaiian, Aloha, United, American, Air Canada, Delta, Japan Airlines, Northwest Airlines or Quantas.